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apache / nuttx-apps / e81227f99daa285cf288fcaa74fcdab6bb5c384c / . / interpreters / minibasic / basic.c
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/****************************************************************************
* apps/interpreters/minibasic/basic.c
*
* Copyright (C) 2016 Gregory Nutt. All rights reserved.
*
* This file was taken from Mini Basic, versino 1.0 developed by Malcolm
* McLean, Leeds University. Mini Basic version 1.0 was released the
* Creative Commons Attribution license which, from my reading, appears to
* be compatible with the NuttX BSD-style license:
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <math.h>
#include <limits.h>
#include <ctype.h>
#include <assert.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration */
#ifndef CONFIG_INTERPRETER_MINIBASIC_IOBUFSIZE
# define CONFIG_INTERPRETER_MINIBASIC_IOBUFSIZE 1024
#endif
#define IOBUFSIZE CONFIG_INTERPRETER_MINIBASIC_IOBUFSIZE
/* Tokens defined */
#define EOS 0
#define VALUE 1
#define PI 2
#define E 3
#define DIV 10
#define MULT 11
#define OPAREN 12
#define CPAREN 13
#define PLUS 14
#define MINUS 15
#define SHRIEK 16
#define COMMA 17
#define MOD 200
#define SYNTAX_ERROR 20
#define EOL 21
#define EQUALS 22
#define STRID 23
#define FLTID 24
#define DIMFLTID 25
#define DIMSTRID 26
#define QUOTE 27
#define GREATER 28
#define LESS 29
#define SEMICOLON 30
#define PRINT 100
#define LET 101
#define DIM 102
#define IF 103
#define THEN 104
#define AND 105
#define OR 106
#define GOTO 107
#define INPUT 108
#define REM 109
#define FOR 110
#define TO 111
#define NEXT 112
#define STEP 113
#define SIN 5
#define COS 6
#define TAN 7
#define LN 8
#define POW 9
#define SQRT 18
#define ABS 201
#define LEN 202
#define ASCII 203
#define ASIN 204
#define ACOS 205
#define ATAN 206
#define INT 207
#define RND 208
#define VAL 209
#define VALLEN 210
#define INSTR 211
#define CHRSTRING 300
#define STRSTRING 301
#define LEFTSTRING 302
#define RIGHTSTRING 303
#define MIDSTRING 304
#define STRINGSTRING 305
/* Relational operators defined */
#define ROP_EQ 1 /* equals */
#define ROP_NEQ 2 /* doesn't equal */
#define ROP_LT 3 /* less than */
#define ROP_LTE 4 /* less than or equals */
#define ROP_GT 5 /* greater than */
#define ROP_GTE 6 /* greater than or equals */
/* Error codes (in BASIC script) defined */
#define ERR_CLEAR 0
#define ERR_SYNTAX 1
#define ERR_OUTOFMEMORY 2
#define ERR_IDTOOLONG 3
#define ERR_NOSUCHVARIABLE 4
#define ERR_BADSUBSCRIPT 5
#define ERR_TOOMANYDIMS 6
#define ERR_TOOMANYINITS 7
#define ERR_BADTYPE 8
#define ERR_TOOMANYFORS 9
#define ERR_NONEXT 10
#define ERR_NOFOR 11
#define ERR_DIVIDEBYZERO 12
#define ERR_NEGLOG 13
#define ERR_NEGSQRT 14
#define ERR_BADSINCOS 15
#define ERR_EOF 16
#define ERR_ILLEGALOFFSET 17
#define ERR_TYPEMISMATCH 18
#define ERR_INPUTTOOLONG 19
#define ERR_BADVALUE 20
#define ERR_NOTINT 21
#define MAXFORS 32 /* Maximum number of nested fors */
/****************************************************************************
* Private Types
****************************************************************************/
struct mb_line_s
{
int no; /* Line number */
FAR const char *str; /* Points to start of line */
};
struct mb_variable_s
{
char id[32]; /* Id of variable */
double dval; /* Its value if a real */
FAR char *sval; /* Its value if a string (malloced) */
};
struct mb_dimvar_s
{
char id[32]; /* Id of dimensioned variable */
int type; /* Its type, STRID or FLTID */
int ndims; /* Number of dimensions */
int dim[5]; /* Dimensions in x y order */
FAR char **str; /* Pointer to string data */
FAR double *dval; /* Pointer to real data */
};
struct mb_lvalue_s
{
int type; /* Type of variable (STRID or FLTID or SYNTAX_ERROR) */
FAR char **sval; /* Pointer to string data */
FAR double *dval; /* Pointer to real data */
};
struct mb_forloop_s
{
char id[32]; /* Id of control variable */
int nextline; /* Line below FOR to which control passes */
double toval; /* Terminal value */
double step; /* Step size */
};
/****************************************************************************
* Private Data
****************************************************************************/
/* NOTE: The use of these globals precludes the use of Mini Basic on
* multiple threads (at least in a flat address environment). If you
* want multiple copies of Mini Basic to run, you would need to:
* (1) Create a new struct mb_state_s that contains all of the following
* as fields.
* (2) Allocate an instance of struct mb_state_s in basic() as part of the
* initialization logic. And,
* (3) Pass the instance of struct mb_state_s to every Mini Basic function.
*/
static struct mb_forloop_s g_forstack[MAXFORS]; /* Stack for for loop control */
static int nfors; /* Number of fors on stack */
static FAR struct mb_variable_s *g_variables; /* The script's variables */
static int g_nvariables; /* Number of variables */
static FAR struct mb_dimvar_s *g_dimvariables; /* Dimensioned arrays */
static int g_ndimvariables; /* Number of dimensioned arrays */
static FAR struct mb_line_s *g_lines; /* List of line starts */
static int nlines; /* Number of BASIC g_lines in program */
static FILE *g_fpin; /* Input stream */
static FILE *g_fpout; /* Output stream */
static FILE *g_fperr; /* Error stream */
static FAR const char *g_string; /* String we are parsing */
static int g_token; /* Current token (lookahead) */
static int g_errorflag; /* Set when error in input encountered */
static char g_iobuffer[IOBUFSIZE]; /* I/O buffer */
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int setup(FAR const char *script);
static void cleanup(void);
static void reporterror(int lineno);
static int findline(int no);
static int line(void);
static void doprint(void);
static void dolet(void);
static void dodim(void);
static int doif(void);
static int dogoto(void);
static void doinput(void);
static void dorem(void);
static int dofor(void);
static int donext(void);
static void lvalue(FAR struct mb_lvalue_s *lv);
static int boolexpr(void);
static int boolfactor(void);
static int relop(void);
static double expr(void);
static double term(void);
static double factor(void);
static double instr(void);
static double variable(void);
static double dimvariable(void);
static FAR struct mb_variable_s *findvariable(FAR const char *id);
static FAR struct mb_dimvar_s *finddimvar(FAR const char *id);
static FAR struct mb_dimvar_s *dimension(FAR const char *id, int ndims, ...);
static FAR void *getdimvar(FAR struct mb_dimvar_s *dv, ...);
static FAR struct mb_variable_s *addfloat(FAR const char *id);
static FAR struct mb_variable_s *addstring(FAR const char *id);
static FAR struct mb_dimvar_s *adddimvar(FAR const char *id);
static FAR char *stringexpr(void);
static FAR char *chrstring(void);
static FAR char *strstring(void);
static FAR char *leftstring(void);
static FAR char *rightstring(void);
static FAR char *midstring(void);
static FAR char *stringstring(void);
static FAR char *stringdimvar(void);
static FAR char *stringvar(void);
static FAR char *stringliteral(void);
static int integer(double x);
static void match(int tok);
static void seterror(int errorcode);
static int getnextline(FAR const char *str);
static int gettoken(FAR const char *str);
static int tokenlen(FAR const char *str, int tokenid);
static int isstring(int tokenid);
static double getvalue(FAR const char *str, FAR int *len);
static void getid(FAR const char *str, FAR char *out, FAR int *len);
static void mystrgrablit(FAR char *dest, FAR const char *src);
static FAR char *mystrend(FAR const char *str, char quote);
static int mystrcount(FAR const char *str, char ch);
static FAR char *mystrdup(FAR const char *str);
static FAR char *mystrconcat(FAR const char *str, FAR const char *cat);
static double factorial(double x);
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: setup
*
* Description:
* Sets up all our globals, including the list of lines.
* Params: script - the script passed by the user
* Returns: 0 on success, -1 on failure
*
*
****************************************************************************/
static int setup(FAR const char *script)
{
int i;
nlines = mystrcount(script, '\n');
g_lines = malloc(nlines * sizeof(struct mb_line_s));
if (!g_lines)
{
if (g_fperr)
{
fprintf(g_fperr, "Out of memory\n");
}
return -1;
}
for (i = 0; i < nlines; i++)
{
if (isdigit(*script))
{
g_lines[i].str = script;
g_lines[i].no = strtol(script, 0, 10);
}
else
{
i--;
nlines--;
}
script = strchr(script, '\n');
script++;
}
if (!nlines)
{
if (g_fperr)
{
fprintf(g_fperr, "Can't read program\n");
}
free(g_lines);
return -1;
}
for (i = 1; i < nlines; i++)
{
if (g_lines[i].no <= g_lines[i - 1].no)
{
if (g_fperr)
{
fprintf(g_fperr, "program lines %d and %d not in order\n",
g_lines[i - 1].no, g_lines[i].no);
}
free(g_lines);
return -1;
}
}
g_nvariables = 0;
g_variables = 0;
g_dimvariables = 0;
g_ndimvariables = 0;
return 0;
}
/****************************************************************************
* Name: cleanup
*
* Description:
* Frees all the memory we have allocated
*
****************************************************************************/
static void cleanup(void)
{
int i;
int ii;
int size;
for (i = 0; i < g_nvariables; i++)
{
if (g_variables[i].sval)
{
free(g_variables[i].sval);
}
}
if (g_variables)
{
free(g_variables);
}
g_variables = 0;
g_nvariables = 0;
for (i = 0; i < g_ndimvariables; i++)
{
if (g_dimvariables[i].type == STRID)
{
if (g_dimvariables[i].str)
{
size = 1;
for (ii = 0; ii < g_dimvariables[i].ndims; ii++)
{
size *= g_dimvariables[i].dim[ii];
}
for (ii = 0; ii < size; ii++)
{
if (g_dimvariables[i].str[ii])
{
free(g_dimvariables[i].str[ii]);
}
}
free(g_dimvariables[i].str);
}
}
else if (g_dimvariables[i].dval)
{
free(g_dimvariables[i].dval);
}
}
if (g_dimvariables)
{
free(g_dimvariables);
}
g_dimvariables = 0;
g_ndimvariables = 0;
if (g_lines)
{
free(g_lines);
}
g_lines = 0;
nlines = 0;
}
/****************************************************************************
* Name: reporterror
*
* Description:
* Frror report function.
* For reporting errors in the user's script.
* Checks the global g_errorflag.
* Writes to g_fperr.
* Params: lineno - the line on which the error occurred
*
****************************************************************************/
static void reporterror(int lineno)
{
if (!g_fperr)
{
return;
}
switch (g_errorflag)
{
case ERR_CLEAR:
assert(0);
break;
case ERR_SYNTAX:
fprintf(g_fperr, "Syntax error line %d\n", lineno);
break;
case ERR_OUTOFMEMORY:
fprintf(g_fperr, "Out of memory line %d\n", lineno);
break;
case ERR_IDTOOLONG:
fprintf(g_fperr, "Identifier too long line %d\n", lineno);
break;
case ERR_NOSUCHVARIABLE:
fprintf(g_fperr, "No such variable line %d\n", lineno);
break;
case ERR_BADSUBSCRIPT:
fprintf(g_fperr, "Bad subscript line %d\n", lineno);
break;
case ERR_TOOMANYDIMS:
fprintf(g_fperr, "Too many dimensions line %d\n", lineno);
break;
case ERR_TOOMANYINITS:
fprintf(g_fperr, "Too many initialisers line %d\n", lineno);
break;
case ERR_BADTYPE:
fprintf(g_fperr, "Illegal type line %d\n", lineno);
break;
case ERR_TOOMANYFORS:
fprintf(g_fperr, "Too many nested fors line %d\n", lineno);
break;
case ERR_NONEXT:
fprintf(g_fperr, "For without matching next line %d\n", lineno);
break;
case ERR_NOFOR:
fprintf(g_fperr, "Next without matching for line %d\n", lineno);
break;
case ERR_DIVIDEBYZERO:
fprintf(g_fperr, "Divide by zero lne %d\n", lineno);
break;
case ERR_NEGLOG:
fprintf(g_fperr, "Negative logarithm line %d\n", lineno);
break;
case ERR_NEGSQRT:
fprintf(g_fperr, "Negative square root line %d\n", lineno);
break;
case ERR_BADSINCOS:
fprintf(g_fperr, "Sine or cosine out of range line %d\n", lineno);
break;
case ERR_EOF:
fprintf(g_fperr, "End of input file %d\n", lineno);
break;
case ERR_ILLEGALOFFSET:
fprintf(g_fperr, "Illegal offset line %d\n", lineno);
break;
case ERR_TYPEMISMATCH:
fprintf(g_fperr, "Type mismatch line %d\n", lineno);
break;
case ERR_INPUTTOOLONG:
fprintf(g_fperr, "Input too long line %d\n", lineno);
break;
case ERR_BADVALUE:
fprintf(g_fperr, "Bad value at line %d\n", lineno);
break;
case ERR_NOTINT:
fprintf(g_fperr, "Not an integer at line %d\n", lineno);
break;
default:
fprintf(g_fperr, "ERROR line %d\n", lineno);
break;
}
}
/****************************************************************************
* Name: findline
*
* Description:
* Binary search for a line
* Params: no - line number to find
* Returns: index of the line, or -1 on fail.
*
****************************************************************************/
static int findline(int no)
{
int high;
int low;
int mid;
low = 0;
high = nlines - 1;
while (high > low + 1)
{
mid = (high + low) / 2;
if (g_lines[mid].no == no)
{
return mid;
}
if (g_lines[mid].no > no)
{
high = mid;
}
else
{
low = mid;
}
}
if (g_lines[low].no == no)
{
mid = low;
}
else if (g_lines[high].no == no)
{
mid = high;
}
else
{
mid = -1;
}
return mid;
}
/****************************************************************************
* Name: line
*
* Description:
* Parse a line. High level parse function
*
****************************************************************************/
static int line(void)
{
int answer = 0;
FAR const char *str;
match(VALUE);
switch (g_token)
{
case PRINT:
doprint();
break;
case LET:
dolet();
break;
case DIM:
dodim();
break;
case IF:
answer = doif();
break;
case GOTO:
answer = dogoto();
break;
case INPUT:
doinput();
break;
case REM:
dorem();
return 0;
case FOR:
answer = dofor();
break;
case NEXT:
answer = donext();
break;
default:
seterror(ERR_SYNTAX);
break;
}
if (g_token != EOS)
{
/* match(VALUE); */
/* check for a newline */
str = g_string;
while (isspace(*str))
{
if (*str == '\n')
{
break;
}
str++;
}
if (*str != '\n')
{
seterror(ERR_SYNTAX);
}
}
return answer;
}
/****************************************************************************
* Name: doprint
*
* Description:
* The PRINT statement
*
****************************************************************************/
static void doprint(void)
{
FAR char *str;
double x;
match(PRINT);
while (1)
{
if (isstring(g_token))
{
str = stringexpr();
if (str)
{
fprintf(g_fpout, "%s", str);
free(str);
}
}
else
{
x = expr();
fprintf(g_fpout, "%g", x);
}
if (g_token == COMMA)
{
fprintf(g_fpout, " ");
match(COMMA);
}
else
{
break;
}
}
if (g_token == SEMICOLON)
{
match(SEMICOLON);
fflush(g_fpout);
}
else
{
fprintf(g_fpout, "\n");
}
}
/****************************************************************************
* Name: dolet
*
* Description:
* The LET statement
*
****************************************************************************/
static void dolet(void)
{
struct mb_lvalue_s lv;
FAR char *temp;
match(LET);
lvalue(&lv);
match(EQUALS);
switch (lv.type)
{
case FLTID:
*lv.dval = expr();
break;
case STRID:
temp = *lv.sval;
*lv.sval = stringexpr();
if (temp)
{
free(temp);
}
break;
default:
break;
}
}
/****************************************************************************
* Name: dodim
*
* Description:
* The DIM statement
*
****************************************************************************/
static void dodim(void)
{
int ndims = 0;
double dims[6];
char name[32];
int len;
FAR struct mb_dimvar_s *dimvar;
int i;
int size = 1;
match(DIM);
switch (g_token)
{
case DIMFLTID:
case DIMSTRID:
getid(g_string, name, &len);
match(g_token);
dims[ndims++] = expr();
while (g_token == COMMA)
{
match(COMMA);
dims[ndims++] = expr();
if (ndims > 5)
{
seterror(ERR_TOOMANYDIMS);
return;
}
}
match(CPAREN);
for (i = 0; i < ndims; i++)
{
if (dims[i] < 0 || dims[i] != (int)dims[i])
{
seterror(ERR_BADSUBSCRIPT);
return;
}
}
switch (ndims)
{
case 1:
dimvar = dimension(name, 1, (int)dims[0]);
break;
case 2:
dimvar = dimension(name, 2, (int)dims[0], (int)dims[1]);
break;
case 3:
dimvar = dimension(name, 3, (int)dims[0],
(int)dims[1], (int)dims[2]);
break;
case 4:
dimvar =
dimension(name, 4, (int)dims[0], (int)dims[1], (int)dims[2],
(int)dims[3]);
break;
case 5:
dimvar =
dimension(name, 5, (int)dims[0], (int)dims[1], (int)dims[2],
(int)dims[3], (int)dims[4]);
break;
}
break;
default:
seterror(ERR_SYNTAX);
return;
}
if (dimvar == 0)
{
/* Out of memory */
seterror(ERR_OUTOFMEMORY);
return;
}
if (g_token == EQUALS)
{
match(EQUALS);
for (i = 0; i < dimvar->ndims; i++)
{
size *= dimvar->dim[i];
}
switch (dimvar->type)
{
case FLTID:
i = 0;
dimvar->dval[i++] = expr();
while (g_token == COMMA && i < size)
{
match(COMMA);
dimvar->dval[i++] = expr();
if (g_errorflag)
{
break;
}
}
break;
case STRID:
i = 0;
if (dimvar->str[i])
{
free(dimvar->str[i]);
}
dimvar->str[i++] = stringexpr();
while (g_token == COMMA && i < size)
{
match(COMMA);
if (dimvar->str[i])
{
free(dimvar->str[i]);
}
dimvar->str[i++] = stringexpr();
if (g_errorflag)
{
break;
}
}
break;
}
if (g_token == COMMA)
{
seterror(ERR_TOOMANYINITS);
}
}
}
/****************************************************************************
* Name: doif
*
* Description:
* The IF statement.
* If jump taken, returns new line no, else returns 0
*
****************************************************************************/
static int doif(void)
{
int condition;
int jump;
match(IF);
condition = boolexpr();
match(THEN);
jump = integer(expr());
if (condition)
{
return jump;
}
else
{
return 0;
}
}
/****************************************************************************
* Name: dogoto
*
* Description:
* The GOTO satement
* Returns new line number
*
****************************************************************************/
static int dogoto(void)
{
match(GOTO);
return integer(expr());
}
/****************************************************************************
* Name: dofor
*
* Description:
* The FOR statement.
*
* Pushes the for stack.
* Returns line to jump to, or -1 to end program
*
****************************************************************************/
static int dofor(void)
{
struct mb_lvalue_s lv;
char id[32];
char nextid[32];
int len;
double initval;
double toval;
double stepval;
FAR const char *savestring;
int answer;
match(FOR);
getid(g_string, id, &len);
lvalue(&lv);
if (lv.type != FLTID)
{
seterror(ERR_BADTYPE);
return -1;
}
match(EQUALS);
initval = expr();
match(TO);
toval = expr();
if (g_token == STEP)
{
match(STEP);
stepval = expr();
}
else
{
stepval = 1.0;
}
*lv.dval = initval;
if (nfors > MAXFORS - 1)
{
seterror(ERR_TOOMANYFORS);
return -1;
}
if ((stepval < 0 && initval < toval) ||
(stepval > 0 && initval > toval))
{
savestring = g_string;
while ((g_string = strchr(g_string, '\n')) != NULL)
{
g_errorflag = 0;
g_token = gettoken(g_string);
match(VALUE);
if (g_token == NEXT)
{
match(NEXT);
if (g_token == FLTID || g_token == DIMFLTID)
{
getid(g_string, nextid, &len);
if (!strcmp(id, nextid))
{
answer = getnextline(g_string);
g_string = savestring;
g_token = gettoken(g_string);
return answer ? answer : -1;
}
}
}
}
seterror(ERR_NONEXT);
return -1;
}
else
{
strlcpy(g_forstack[nfors].id, id, sizeof(g_forstack[nfors].id));
g_forstack[nfors].nextline = getnextline(g_string);
g_forstack[nfors].step = stepval;
g_forstack[nfors].toval = toval;
nfors++;
return 0;
}
}
/****************************************************************************
* Name: donext
*
* Description:
* The NEXT statement
* Updates the counting index, and returns line to jump to
*
****************************************************************************/
static int donext(void)
{
char id[32];
int len;
struct mb_lvalue_s lv;
match(NEXT);
if (nfors)
{
getid(g_string, id, &len);
lvalue(&lv);
if (lv.type != FLTID)
{
seterror(ERR_BADTYPE);
return -1;
}
*lv.dval += g_forstack[nfors - 1].step;
if ((g_forstack[nfors - 1].step < 0 &&
*lv.dval < g_forstack[nfors - 1].toval) ||
(g_forstack[nfors - 1].step > 0 &&
*lv.dval > g_forstack[nfors - 1].toval))
{
nfors--;
return 0;
}
else
{
return g_forstack[nfors - 1].nextline;
}
}
else
{
seterror(ERR_NOFOR);
return -1;
}
}
/****************************************************************************
* Name: doinput
*
* Description:
* The INPUT statement
*
****************************************************************************/
static void doinput(void)
{
struct mb_lvalue_s lv;
FAR char *end;
match(INPUT);
lvalue(&lv);
switch (lv.type)
{
case FLTID:
{
FAR char *ptr;
int nch;
/* Copy floating point number to a g_iobuffer. Skip over leading
* spaces and terminate with a NUL when a space, tab, newline, EOF,
* or comma is detected.
*/
for (nch = 0, ptr = g_iobuffer; nch < (IOBUFSIZE - 1); nch++)
{
int ch = fgetc(g_fpin);
if (ch == EOF)
{
seterror(ERR_EOF);
return;
}
if (ch == ' ' || ch == '\t' || ch == ',' || ch == '\n')
{
ungetc(ch, g_fpin);
break;
}
}
*ptr = '\0';
/* Use strtod() to get the floating point value from the substring
* in g_iobuffer.
*/
*lv.dval = strtod(g_iobuffer, &ptr);
if (ptr == g_iobuffer)
{
seterror(ERR_SYNTAX);
return;
}
}
break;
case STRID:
{
if (*lv.sval)
{
free(*lv.sval);
*lv.sval = NULL;
}
if (fgets(g_iobuffer, IOBUFSIZE, g_fpin) == 0)
{
seterror(ERR_EOF);
return;
}
end = strchr(g_iobuffer, '\n');
if (!end)
{
seterror(ERR_INPUTTOOLONG);
return;
}
*end = 0;
*lv.sval = mystrdup(g_iobuffer);
if (!*lv.sval)
{
seterror(ERR_OUTOFMEMORY);
return;
}
}
break;
default:
break;
}
}
/****************************************************************************
* Name: dorem
*
* Description:
* The REM statement.
* Note is unique as the rest of the line is not parsed
*
****************************************************************************/
static void dorem(void)
{
match(REM);
}
/****************************************************************************
* Name: lvalue
*
* Description:
* Get an lvalue from the environment
* Params: lv - structure to fill.
* Notes: missing variables (but not out of range subscripts)
* are added to the variable list.
*
****************************************************************************/
static void lvalue(FAR struct mb_lvalue_s *lv)
{
char name[32];
int len;
FAR struct mb_variable_s *var;
FAR struct mb_dimvar_s *dimvar;
int index[5];
FAR void *valptr = 0;
int type;
lv->type = SYNTAX_ERROR;
lv->dval = NULL;
lv->sval = NULL;
switch (g_token)
{
case FLTID:
{
getid(g_string, name, &len);
match(FLTID);
var = findvariable(name);
if (!var)
{
var = addfloat(name);
}
if (!var)
{
seterror(ERR_OUTOFMEMORY);
return;
}
lv->type = FLTID;
lv->dval = &var->dval;
lv->sval = NULL;
}
break;
case STRID:
{
getid(g_string, name, &len);
match(STRID);
var = findvariable(name);
if (!var)
{
var = addstring(name);
}
if (!var)
{
seterror(ERR_OUTOFMEMORY);
return;
}
lv->type = STRID;
lv->sval = &var->sval;
lv->dval = NULL;
}
break;
case DIMFLTID:
case DIMSTRID:
{
type = (g_token == DIMFLTID) ? FLTID : STRID;
getid(g_string, name, &len);
match(g_token);
dimvar = finddimvar(name);
if (dimvar)
{
switch (dimvar->ndims)
{
case 1:
{
index[0] = integer(expr());
if (g_errorflag == 0)
{
valptr = getdimvar(dimvar, index[0]);
}
}
break;
case 2:
{
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
if (g_errorflag == 0)
{
valptr = getdimvar(dimvar, index[0], index[1]);
}
}
break;
case 3:
{
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
match(COMMA);
index[2] = integer(expr());
if (g_errorflag == 0)
{
valptr = getdimvar(dimvar, index[0],
index[1], index[2]);
}
}
break;
case 4:
{
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
match(COMMA);
index[2] = integer(expr());
match(COMMA);
index[3] = integer(expr());
if (g_errorflag == 0)
{
valptr = getdimvar(dimvar, index[0],
index[1], index[2], index[3]);
}
}
break;
case 5:
{
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
match(COMMA);
index[2] = integer(expr());
match(COMMA);
index[3] = integer(expr());
match(COMMA);
index[4] = integer(expr());
if (g_errorflag == 0)
{
valptr = getdimvar(dimvar, index[0],
index[1], index[2], index[3]);
}
}
break;
}
match(CPAREN);
}
else
{
seterror(ERR_NOSUCHVARIABLE);
return;
}
if (valptr)
{
lv->type = type;
if (type == FLTID)
{
lv->dval = valptr;
}
else if (type == STRID)
{
lv->sval = valptr;
}
else
{
assert(0);
}
}
}
break;
default:
seterror(ERR_SYNTAX);
}
}
/****************************************************************************
* Name: boolexpr
*
* Description:
* Parse a boolean expression
* Consists of expressions or strings and relational operators,
* and parentheses
*
****************************************************************************/
static int boolexpr(void)
{
int left;
int right;
left = boolfactor();
while (1)
{
switch (g_token)
{
case AND:
match(AND);
right = boolexpr();
return (left && right) ? 1 : 0;
case OR:
match(OR);
right = boolexpr();
return (left || right) ? 1 : 0;
default:
return left;
}
}
}
/****************************************************************************
* Name: boolfactor
*
* Description:
* Boolean factor, consists of expression relop expression
* or string relop string, or ( boolexpr() )
*
****************************************************************************/
static int boolfactor(void)
{
int answer;
double left;
double right;
int op;
FAR char *strleft;
FAR char *strright;
int cmp;
switch (g_token)
{
case OPAREN:
match(OPAREN);
answer = boolexpr();
match(CPAREN);
break;
default:
if (isstring(g_token))
{
strleft = stringexpr();
op = relop();
strright = stringexpr();
if (!strleft || !strright)
{
if (strleft)
{
free(strleft);
}
if (strright)
{
free(strright);
}
return 0;
}
cmp = strcmp(strleft, strright);
switch (op)
{
case ROP_EQ:
answer = cmp == 0 ? 1 : 0;
break;
case ROP_NEQ:
answer = cmp == 0 ? 0 : 1;
break;
case ROP_LT:
answer = cmp < 0 ? 1 : 0;
break;
case ROP_LTE:
answer = cmp <= 0 ? 1 : 0;
break;
case ROP_GT:
answer = cmp > 0 ? 1 : 0;
break;
case ROP_GTE:
answer = cmp >= 0 ? 1 : 0;
break;
default:
answer = 0;
}
free(strleft);
free(strright);
}
else
{
left = expr();
op = relop();
right = expr();
switch (op)
{
case ROP_EQ:
answer = (left == right) ? 1 : 0;
break;
case ROP_NEQ:
answer = (left != right) ? 1 : 0;
break;
case ROP_LT:
answer = (left < right) ? 1 : 0;
break;
case ROP_LTE:
answer = (left <= right) ? 1 : 0;
break;
case ROP_GT:
answer = (left > right) ? 1 : 0;
break;
case ROP_GTE:
answer = (left >= right) ? 1 : 0;
break;
default:
g_errorflag = 1;
return 0;
}
}
}
return answer;
}
/****************************************************************************
* Name: relop
*
* Description:
* Get a relational operator
* Returns operator parsed or SYNTAX_ERROR
*
****************************************************************************/
static int relop(void)
{
switch (g_token)
{
case EQUALS:
match(EQUALS);
return ROP_EQ;
case GREATER:
match(GREATER);
if (g_token == EQUALS)
{
match(EQUALS);
return ROP_GTE;
}
return ROP_GT;
case LESS:
match(LESS);
if (g_token == EQUALS)
{
match(EQUALS);
return ROP_LTE;
}
else if (g_token == GREATER)
{
match(GREATER);
return ROP_NEQ;
}
return ROP_LT;
default:
seterror(ERR_SYNTAX);
return SYNTAX_ERROR;
}
}
/****************************************************************************
* Name: expr
*
* Description:
* Parses an expression
*
****************************************************************************/
static double expr(void)
{
double left;
double right;
left = term();
while (1)
{
switch (g_token)
{
case PLUS:
match(PLUS);
right = term();
left += right;
break;
case MINUS:
match(MINUS);
right = term();
left -= right;
break;
default:
return left;
}
}
}
/****************************************************************************
* Name: term
*
* Description:
* Parses a term
*
****************************************************************************/
static double term(void)
{
double left;
double right;
left = factor();
while (1)
{
switch (g_token)
{
case MULT:
match(MULT);
right = factor();
left *= right;
break;
case DIV:
match(DIV);
right = factor();
if (right != 0.0)
{
left /= right;
}
else
{
seterror(ERR_DIVIDEBYZERO);
}
break;
case MOD:
match(MOD);
right = factor();
left = fmod(left, right);
break;
default:
return left;
}
}
}
/****************************************************************************
* Name: factor
*
* Description:
* Parses a factor
*
****************************************************************************/
static double factor(void)
{
double answer = 0;
FAR char *str;
FAR char *end;
int len;
switch (g_token)
{
case OPAREN:
match(OPAREN);
answer = expr();
match(CPAREN);
break;
case VALUE:
answer = getvalue(g_string, &len);
match(VALUE);
break;
case MINUS:
match(MINUS);
answer = -factor();
break;
case FLTID:
answer = variable();
break;
case DIMFLTID:
answer = dimvariable();
break;
case E:
answer = exp(1.0);
match(E);
break;
case PI:
answer = acos(0.0) * 2.0;
match(PI);
break;
case SIN:
match(SIN);
match(OPAREN);
answer = expr();
match(CPAREN);
answer = sin(answer);
break;
case COS:
match(COS);
match(OPAREN);
answer = expr();
match(CPAREN);
answer = cos(answer);
break;
case TAN:
match(TAN);
match(OPAREN);
answer = expr();
match(CPAREN);
answer = tan(answer);
break;
case LN:
match(LN);
match(OPAREN);
answer = expr();
match(CPAREN);
if (answer > 0)
{
answer = log(answer);
}
else
{
seterror(ERR_NEGLOG);
}
break;
case POW:
match(POW);
match(OPAREN);
answer = expr();
match(COMMA);
answer = pow(answer, expr());
match(CPAREN);
break;
case SQRT:
match(SQRT);
match(OPAREN);
answer = expr();
match(CPAREN);
if (answer >= 0.0)
{
answer = sqrt(answer);
}
else
{
seterror(ERR_NEGSQRT);
}
break;
case ABS:
match(ABS);
match(OPAREN);
answer = expr();
match(CPAREN);
answer = fabs(answer);
break;
case LEN:
match(LEN);
match(OPAREN);
str = stringexpr();
match(CPAREN);
if (str)
{
answer = strlen(str);
free(str);
}
else
{
answer = 0;
}
break;
case ASCII:
match(ASCII);
match(OPAREN);
str = stringexpr();
match(CPAREN);
if (str)
{
answer = *str;
free(str);
}
else
{
answer = 0;
}
break;
case ASIN:
match(ASIN);
match(OPAREN);
answer = expr();
match(CPAREN);
if (answer >= -1 && answer <= 1)
{
answer = asin(answer);
}
else
{
seterror(ERR_BADSINCOS);
}
break;
case ACOS:
match(ACOS);
match(OPAREN);
answer = expr();
match(CPAREN);
if (answer >= -1 && answer <= 1)
{
answer = acos(answer);
}
else
{
seterror(ERR_BADSINCOS);
}
break;
case ATAN:
match(ATAN);
match(OPAREN);
answer = expr();
match(CPAREN);
answer = atan(answer);
break;
case INT:
match(INT);
match(OPAREN);
answer = expr();
match(CPAREN);
answer = floor(answer);
break;
case RND:
match(RND);
match(OPAREN);
answer = expr();
match(CPAREN);
answer = integer(answer);
if (answer > 1)
{
answer = floor(rand() / (RAND_MAX + 1.0) * answer);
}
else if (answer == 1)
{
answer = rand() / (RAND_MAX + 1.0);
}
else
{
if (answer < 0)
{
srand((unsigned)-answer);
}
answer = 0;
}
break;
case VAL:
match(VAL);
match(OPAREN);
str = stringexpr();
match(CPAREN);
if (str)
{
answer = strtod(str, 0);
free(str);
}
else
{
answer = 0;
}
break;
case VALLEN:
match(VALLEN);
match(OPAREN);
str = stringexpr();
match(CPAREN);
if (str)
{
strtod(str, &end);
answer = end - str;
free(str);
}
else
{
answer = 0.0;
}
break;
case INSTR:
answer = instr();
break;
default:
if (isstring(g_token))
{
seterror(ERR_TYPEMISMATCH);
}
else
{
seterror(ERR_SYNTAX);
}
break;
}
while (g_token == SHRIEK)
{
match(SHRIEK);
answer = factorial(answer);
}
return answer;
}
/****************************************************************************
* Name: instr
*
* Description:
* Calculate the INSTR() function.
*
****************************************************************************/
static double instr(void)
{
FAR char *str;
FAR char *substr;
FAR char *end;
double answer = 0;
int offset;
match(INSTR);
match(OPAREN);
str = stringexpr();
match(COMMA);
substr = stringexpr();
match(COMMA);
offset = integer(expr());
offset--;
match(CPAREN);
if (!str || !substr)
{
if (str)
{
free(str);
}
if (substr)
{
free(substr);
}
return 0;
}
if (offset >= 0 && offset < (int)strlen(str))
{
end = strstr(str + offset, substr);
if (end)
{
answer = end - str + 1.0;
}
}
free(str);
free(substr);
return answer;
}
/****************************************************************************
* Name: variable
*
* Description:
* Get the value of a scalar variable from string
* matches FLTID
*
*
****************************************************************************/
static double variable(void)
{
FAR struct mb_variable_s *var;
char id[32];
int len;
getid(g_string, id, &len);
match(FLTID);
var = findvariable(id);
if (var)
{
return var->dval;
}
else
{
seterror(ERR_NOSUCHVARIABLE);
return 0.0;
}
}
/****************************************************************************
* Name: dimvariable
*
* Description:
* Get value of a dimensioned variable from string.
* matches DIMFLTID
*
****************************************************************************/
static double dimvariable(void)
{
FAR struct mb_dimvar_s *dimvar;
char id[32];
int len;
int index[5];
FAR double *answer = NULL;
getid(g_string, id, &len);
match(DIMFLTID);
dimvar = finddimvar(id);
if (!dimvar)
{
seterror(ERR_NOSUCHVARIABLE);
return 0.0;
}
if (dimvar)
{
switch (dimvar->ndims)
{
case 1:
index[0] = integer(expr());
answer = getdimvar(dimvar, index[0]);
break;
case 2:
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
answer = getdimvar(dimvar, index[0], index[1]);
break;
case 3:
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
match(COMMA);
index[2] = integer(expr());
answer = getdimvar(dimvar, index[0], index[1], index[2]);
break;
case 4:
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
match(COMMA);
index[2] = integer(expr());
match(COMMA);
index[3] = integer(expr());
answer = getdimvar(dimvar, index[0], index[1], index[2], index[3]);
break;
case 5:
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
match(COMMA);
index[2] = integer(expr());
match(COMMA);
index[3] = integer(expr());
match(COMMA);
index[4] = integer(expr());
answer = getdimvar(dimvar, index[0], index[1],
index[2], index[3], index[4]);
break;
}
match(CPAREN);
}
if (answer != NULL)
{
return *answer;
}
return 0.0;
}
/****************************************************************************
* Name: findvariable
*
* Description:
* Find a scalar variable invariables list
* Params: id - id to get
* Returns: pointer to that entry, 0 on fail
*
****************************************************************************/
static FAR struct mb_variable_s *findvariable(FAR const char *id)
{
int i;
for (i = 0; i < g_nvariables; i++)
{
if (!strcmp(g_variables[i].id, id))
{
return &g_variables[i];
}
}
return 0;
}
/****************************************************************************
* Name: finddimvar
*
* Description:
* Get a dimensioned array by name
* Params: id (includes opening parenthesis)
* Returns: pointer to array entry or 0 on fail
*
****************************************************************************/
static struct mb_dimvar_s *finddimvar(FAR const char *id)
{
int i;
for (i = 0; i < g_ndimvariables; i++)
{
if (!strcmp(g_dimvariables[i].id, id))
{
return &g_dimvariables[i];
}
}
return 0;
}
/****************************************************************************
* Name: dimension
*
* Description:
* Dimension an array.
* Params: id - the id of the array (include leading ()
* ndims - number of dimension (1-5)
* ... - integers giving dimension size,
*
****************************************************************************/
static FAR struct mb_dimvar_s *dimension(FAR const char *id, int ndims, ...)
{
FAR struct mb_dimvar_s *dv;
va_list vargs;
int size = 1;
int oldsize = 1;
int i;
int dimensions[5];
FAR double *dtemp;
FAR char **stemp;
assert(ndims <= 5);
if (ndims > 5)
{
return 0;
}
dv = finddimvar(id);
if (!dv)
{
dv = adddimvar(id);
}
if (!dv)
{
seterror(ERR_OUTOFMEMORY);
return 0;
}
if (dv->ndims)
{
for (i = 0; i < dv->ndims; i++)
{
oldsize *= dv->dim[i];
}
}
else
{
oldsize = 0;
}
va_start(vargs, ndims);
for (i = 0; i < ndims; i++)
{
dimensions[i] = va_arg(vargs, int);
size *= dimensions[i];
}
va_end(vargs);
switch (dv->type)
{
case FLTID:
dtemp = realloc(dv->dval, size * sizeof(double));
if (dtemp)
{
dv->dval = dtemp;
}
else
{
seterror(ERR_OUTOFMEMORY);
return 0;
}
break;
case STRID:
if (dv->str)
{
for (i = size; i < oldsize; i++)
{
if (dv->str[i])
{
free(dv->str[i]);
dv->str[i] = 0;
}
}
}
stemp = realloc(dv->str, size * sizeof(char *));
if (stemp)
{
dv->str = stemp;
for (i = oldsize; i < size; i++)
{
dv->str[i] = 0;
}
}
else
{
for (i = 0; i < oldsize; i++)
{
if (dv->str[i])
{
free(dv->str[i]);
dv->str[i] = 0;
}
}
seterror(ERR_OUTOFMEMORY);
return 0;
}
break;
default:
assert(0);
}
for (i = 0; i < 5; i++)
{
dv->dim[i] = dimensions[i];
}
dv->ndims = ndims;
return dv;
}
/****************************************************************************
* Name: getdimvar
*
* Description:
* Get the address of a dimensioned array element.
* Works for both string and real arrays.
* Params: dv - the array's entry in variable list
* ... - integers telling which array element to get
* Returns: the address of that element, 0 on fail
*
****************************************************************************/
static FAR void *getdimvar(FAR struct mb_dimvar_s *dv, ...)
{
va_list vargs;
int index[5];
int i;
FAR void *answer = 0;
va_start(vargs, dv);
for (i = 0; i < dv->ndims; i++)
{
index[i] = va_arg(vargs, int);
index[i]--;
}
va_end(vargs);
for (i = 0; i < dv->ndims; i++)
{
if (index[i] >= dv->dim[i] || index[i] < 0)
{
seterror(ERR_BADSUBSCRIPT);
return 0;
}
}
if (dv->type == FLTID)
{
switch (dv->ndims)
{
case 1:
answer = &dv->dval[index[0]];
break;
case 2:
answer = &dv->dval[index[1] * dv->dim[0] + index[0]];
break;
case 3:
answer = &dv->dval[index[2] * (dv->dim[0] * dv->dim[1])
+ index[1] * dv->dim[0] + index[0]];
break;
case 4:
answer =
&dv->dval[index[3] * (dv->dim[0] + dv->dim[1] + dv->dim[2]) +
index[2] * (dv->dim[0] * dv->dim[1]) +
index[1] * dv->dim[0] + index[0]];
break;
case 5:
answer =
&dv->dval[index[4] *
(dv->dim[0] + dv->dim[1] + dv->dim[2] +
dv->dim[3]) + index[3] * (dv->dim[0] + dv->dim[1] +
dv->dim[2]) +
index[2] * (dv->dim[0] + dv->dim[1]) +
index[1] * dv->dim[0] + index[0]];
break;
}
}
else if (dv->type == STRID)
{
switch (dv->ndims)
{
case 1:
answer = &dv->str[index[0]];
break;
case 2:
answer = &dv->str[index[1] * dv->dim[0] + index[0]];
break;
case 3:
answer = &dv->str[index[2] * (dv->dim[0] * dv->dim[1])
+ index[1] * dv->dim[0] + index[0]];
break;
case 4:
answer =
&dv->str[index[3] * (dv->dim[0] + dv->dim[1] + dv->dim[2]) +
index[2] * (dv->dim[0] * dv->dim[1]) +
index[1] * dv->dim[0] + index[0]];
break;
case 5:
answer =
&dv->str[index[4] *
(dv->dim[0] + dv->dim[1] + dv->dim[2] + dv->dim[3]) +
index[3] * (dv->dim[0] + dv->dim[1] + dv->dim[2]) +
index[2] * (dv->dim[0] + dv->dim[1]) +
index[1] * dv->dim[0] + index[0]];
break;
}
}
return answer;
}
/****************************************************************************
* Name: addfloat
*
* Description:
* Add a real variable to our variable list
* Params: id - id of variable to add.
* Returns: pointer to new entry in table
*
****************************************************************************/
static FAR struct mb_variable_s *addfloat(FAR const char *id)
{
FAR struct mb_variable_s *vars;
vars =
realloc(g_variables, (g_nvariables + 1) * sizeof(struct mb_variable_s));
if (vars)
{
g_variables = vars;
strlcpy(g_variables[g_nvariables].id, id,
sizeof(g_variables[g_nvariables].id));
g_variables[g_nvariables].dval = 0.0;
g_variables[g_nvariables].sval = NULL;
g_nvariables++;
return &g_variables[g_nvariables - 1];
}
else
{
seterror(ERR_OUTOFMEMORY);
}
return 0;
}
/****************************************************************************
* Name: addstring
*
* Description:
* Add a string variable to table.
* Params: id - id of variable to get (including trailing $)
* Returns: pointer to new entry in table, 0 on fail.
*
****************************************************************************/
static FAR struct mb_variable_s *addstring(FAR const char *id)
{
FAR struct mb_variable_s *vars;
vars =
realloc(g_variables, (g_nvariables + 1) * sizeof(struct mb_variable_s));
if (vars)
{
g_variables = vars;
strlcpy(g_variables[g_nvariables].id, id,
sizeof(g_variables[g_nvariables].id));
g_variables[g_nvariables].sval = NULL;
g_variables[g_nvariables].dval = 0.0;
g_nvariables++;
return &g_variables[g_nvariables - 1];
}
else
{
seterror(ERR_OUTOFMEMORY);
}
return 0;
}
/****************************************************************************
* Name: adddimvar
*
* Description:
* Add a new array to our symbol table.
* Params: id - id of array (include leading ()
* Returns: pointer to new entry, 0 on fail.
*
****************************************************************************/
static FAR struct mb_dimvar_s *adddimvar(FAR const char *id)
{
FAR struct mb_dimvar_s *vars;
vars = realloc(g_dimvariables,
(g_ndimvariables + 1) * sizeof(struct mb_dimvar_s));
if (vars)
{
g_dimvariables = vars;
strlcpy(g_dimvariables[g_ndimvariables].id, id,
sizeof(g_dimvariables[g_ndimvariables].id));
g_dimvariables[g_ndimvariables].dval = NULL;
g_dimvariables[g_ndimvariables].str = NULL;
g_dimvariables[g_ndimvariables].ndims = 0;
g_dimvariables[g_ndimvariables].type = strchr(id, '$') ? STRID : FLTID;
g_ndimvariables++;
return &g_dimvariables[g_ndimvariables - 1];
}
else
{
seterror(ERR_OUTOFMEMORY);
}
return 0;
}
/****************************************************************************
* Name: stringexpr
*
* Description:
* High level string parsing function.
* Returns: a malloced pointer, or 0 on error condition.
* caller must free!
*
****************************************************************************/
static FAR char *stringexpr(void)
{
FAR char *left;
FAR char *right;
FAR char *temp;
switch (g_token)
{
case DIMSTRID:
left = mystrdup(stringdimvar());
break;
case STRID:
left = mystrdup(stringvar());
break;
case QUOTE:
left = stringliteral();
break;
case CHRSTRING:
left = chrstring();
break;
case STRSTRING:
left = strstring();
break;
case LEFTSTRING:
left = leftstring();
break;
case RIGHTSTRING:
left = rightstring();
break;
case MIDSTRING:
left = midstring();
break;
case STRINGSTRING:
left = stringstring();
break;
default:
if (!isstring(g_token))
{
seterror(ERR_TYPEMISMATCH);
}
else
{
seterror(ERR_SYNTAX);
}
return mystrdup("");
}
if (!left)
{
seterror(ERR_OUTOFMEMORY);
return 0;
}
switch (g_token)
{
case PLUS:
match(PLUS);
right = stringexpr();
if (right)
{
temp = mystrconcat(left, right);
free(right);
if (temp)
{
free(left);
left = temp;
}
else
{
seterror(ERR_OUTOFMEMORY);
}
}
else
{
seterror(ERR_OUTOFMEMORY);
}
break;
default:
return left;
}
return left;
}
/****************************************************************************
* Name: chrstring
*
* Description:
* Parse the CHR$ token
*
****************************************************************************/
static FAR char *chrstring(void)
{
double x;
FAR char *answer;
match(CHRSTRING);
match(OPAREN);
x = integer(expr());
match(CPAREN);
g_iobuffer[0] = (char)x;
g_iobuffer[1] = 0;
answer = mystrdup(g_iobuffer);
if (!answer)
{
seterror(ERR_OUTOFMEMORY);
}
return answer;
}
/****************************************************************************
* Name: strstring
*
* Description:
* Parse the STR$ token
*
****************************************************************************/
static FAR char *strstring(void)
{
double x;
FAR char *answer;
match(STRSTRING);
match(OPAREN);
x = expr();
match(CPAREN);
snprintf(g_iobuffer, sizeof(g_iobuffer), "%g", x);
answer = mystrdup(g_iobuffer);
if (!answer)
{
seterror(ERR_OUTOFMEMORY);
}
return answer;
}
/****************************************************************************
* Name: leftstring
*
* Description:
* Parse the LEFT$ token
*
****************************************************************************/
static FAR char *leftstring(void)
{
FAR char *str;
int x;
FAR char *answer;
match(LEFTSTRING);
match(OPAREN);
str = stringexpr();
if (!str)
{
return 0;
}
match(COMMA);
x = integer(expr());
match(CPAREN);
if (x > (int)strlen(str))
{
return str;
}
if (x < 0)
{
seterror(ERR_ILLEGALOFFSET);
return str;
}
str[x] = 0;
answer = mystrdup(str);
free(str);
if (!answer)
{
seterror(ERR_OUTOFMEMORY);
}
return answer;
}
/****************************************************************************
* Name: rightstring
*
* Description:
* Parse the RIGHT$ token
*
****************************************************************************/
static FAR char *rightstring(void)
{
int x;
FAR char *str;
FAR char *answer;
match(RIGHTSTRING);
match(OPAREN);
str = stringexpr();
if (!str)
{
return 0;
}
match(COMMA);
x = integer(expr());
match(CPAREN);
if (x > (int)strlen(str))
{
return str;
}
if (x < 0)
{
seterror(ERR_ILLEGALOFFSET);
return str;
}
answer = mystrdup(&str[strlen(str) - x]);
free(str);
if (!answer)
{
seterror(ERR_OUTOFMEMORY);
}
return answer;
}
/****************************************************************************
* Name: midstring
*
* Description:
* Parse the MID$ token
*
****************************************************************************/
static FAR char *midstring(void)
{
FAR char *str;
int x;
int len;
FAR char *answer;
FAR char *temp;
match(MIDSTRING);
match(OPAREN);
str = stringexpr();
match(COMMA);
x = integer(expr());
match(COMMA);
len = integer(expr());
match(CPAREN);
if (!str)
{
return 0;
}
if (len == -1)
{
len = strlen(str) - x + 1;
}
if (x > (int)strlen(str) || len < 1)
{
free(str);
answer = mystrdup("");
if (!answer)
{
seterror(ERR_OUTOFMEMORY);
}
return answer;
}
if (x < 1.0)
{
seterror(ERR_ILLEGALOFFSET);
return str;
}
temp = &str[x - 1];
answer = malloc(len + 1);
if (!answer)
{
seterror(ERR_OUTOFMEMORY);
return str;
}
strlcpy(answer, temp, len + 1);
free(str);
return answer;
}
/****************************************************************************
* Name: stringstring
*
* Description:
* Parse the string$ token
*
****************************************************************************/
static FAR char *stringstring(void)
{
int x;
FAR char *str;
FAR char *answer;
int len;
int N;
int i;
match(STRINGSTRING);
match(OPAREN);
x = integer(expr());
match(COMMA);
str = stringexpr();
match(CPAREN);
if (!str)
{
return 0;
}
N = x;
if (N < 1)
{
free(str);
answer = mystrdup("");
if (!answer)
{
seterror(ERR_OUTOFMEMORY);
}
return answer;
}
len = strlen(str);
answer = malloc(N * len + 1);
if (!answer)
{
free(str);
seterror(ERR_OUTOFMEMORY);
return 0;
}
for (i = 0; i < N; i++)
{
strlcpy(answer + len * i, str, (N - i) * len + 1);
}
free(str);
return answer;
}
/****************************************************************************
* Name: stringdimvar
*
* Description:
* Read a dimensioned string variable from input.
* Returns: pointer to string (not malloced)
*
****************************************************************************/
static FAR char *stringdimvar(void)
{
char id[32];
int len;
FAR struct mb_dimvar_s *dimvar;
FAR char **answer = NULL;
int index[5];
getid(g_string, id, &len);
match(DIMSTRID);
dimvar = finddimvar(id);
if (dimvar)
{
switch (dimvar->ndims)
{
case 1:
index[0] = integer(expr());
answer = getdimvar(dimvar, index[0]);
break;
case 2:
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
answer = getdimvar(dimvar, index[0], index[1]);
break;
case 3:
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
match(COMMA);
index[2] = integer(expr());
answer = getdimvar(dimvar, index[0], index[1], index[2]);
break;
case 4:
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
match(COMMA);
index[2] = integer(expr());
match(COMMA);
index[3] = integer(expr());
answer = getdimvar(dimvar, index[0], index[1], index[2], index[3]);
break;
case 5:
index[0] = integer(expr());
match(COMMA);
index[1] = integer(expr());
match(COMMA);
index[2] = integer(expr());
match(COMMA);
index[3] = integer(expr());
match(COMMA);
index[4] = integer(expr());
answer =
getdimvar(dimvar, index[0], index[1],
index[2], index[3], index[4]);
break;
}
match(CPAREN);
}
else
{
seterror(ERR_NOSUCHVARIABLE);
}
if (!g_errorflag)
{
if (answer != NULL && *answer != NULL)
{
return *answer;
}
}
return "";
}
/****************************************************************************
* Name: stringvar
*
* Description:
* Parse a string variable.
* Returns: pointer to string (not malloced)
*
****************************************************************************/
static FAR char *stringvar(void)
{
char id[32];
int len;
FAR struct mb_variable_s *var;
getid(g_string, id, &len);
match(STRID);
var = findvariable(id);
if (var)
{
if (var->sval)
{
return var->sval;
}
return "";
}
seterror(ERR_NOSUCHVARIABLE);
return "";
}
/****************************************************************************
* Name: stringliteral
*
* Description:
* Parse a string literal
* Returns: malloced string literal
* Notes: newlines aren't allowed in literals, but blind
* concatenation across newlines is.
*
****************************************************************************/
static FAR char *stringliteral(void)
{
int len = 1;
FAR char *answer = 0;
FAR char *temp;
FAR char *substr;
FAR char *end;
while (g_token == QUOTE)
{
while (isspace(*g_string))
{
g_string++;
}
end = mystrend(g_string, '"');
if (end)
{
len = end - g_string;
substr = malloc(len);
if (!substr)
{
seterror(ERR_OUTOFMEMORY);
return answer;
}
mystrgrablit(substr, g_string);
if (answer)
{
temp = mystrconcat(answer, substr);
free(substr);
free(answer);
answer = temp;
if (!answer)
{
seterror(ERR_OUTOFMEMORY);
return answer;
}
}
else
{
answer = substr;
}
g_string = end;
}
else
{
seterror(ERR_SYNTAX);
return answer;
}
match(QUOTE);
}
return answer;
}
/****************************************************************************
* Name: integer
*
* Description:
* Cast a double to an integer, triggering errors if out of range
*
****************************************************************************/
static int integer(double x)
{
if (x < INT_MIN || x > INT_MAX)
{
seterror(ERR_BADVALUE);
}
if (x != floor(x))
{
seterror(ERR_NOTINT);
}
return (int)x;
}
/****************************************************************************
* Name: match
*
* Description:
* Check that we have a token of the passed type (if not set g_errorflag)
* Move parser on to next token. Sets token and string.
*
****************************************************************************/
static void match(int tok)
{
if (g_token != tok)
{
seterror(ERR_SYNTAX);
return;
}
while (isspace(*g_string))
{
g_string++;
}
g_string += tokenlen(g_string, g_token);
g_token = gettoken(g_string);
if (g_token == SYNTAX_ERROR)
{
seterror(ERR_SYNTAX);
}
}
/****************************************************************************
* Name: seterror
*
* Description:
* Set the errorflag.
* Params: errorcode - the error.
* Notes: ignores error cascades
*
****************************************************************************/
static void seterror(int errorcode)
{
if (g_errorflag == 0 || errorcode == 0)
{
g_errorflag = errorcode;
}
}
/****************************************************************************
* Name: getnextline
*
* Description:
* Get the next line number
* Params: str - pointer to parse string
* Returns: line no of next line, 0 if end
* Notes: goes to newline, then finds
* first line starting with a digit.
*
****************************************************************************/
static int getnextline(FAR const char *str)
{
while (*str)
{
while (*str && *str != '\n')
{
str++;
}
if (*str == 0)
{
return 0;
}
str++;
if (isdigit(*str))
{
return atoi(str);
}
}
return 0;
}
/****************************************************************************
* Name: gettoken
*
* Description:
* Get a token from the string
* Params: str - string to read token from
* Notes: ignores white space between tokens
*
****************************************************************************/
static int gettoken(FAR const char *str)
{
while (isspace(*str))
{
str++;
}
if (isdigit(*str))
{
return VALUE;
}
switch (*str)
{
case 0:
return EOS;
case '\n':
return EOL;
case '/':
return DIV;
case '*':
return MULT;
case '(':
return OPAREN;
case ')':
return CPAREN;
case '+':
return PLUS;
case '-':
return MINUS;
case '!':
return SHRIEK;
case ',':
return COMMA;
case ';':
return SEMICOLON;
case '"':
return QUOTE;
case '=':
return EQUALS;
case '<':
return LESS;
case '>':
return GREATER;
default:
if (!strncmp(str, "e", 1) && !isalnum(str[1]))
{
return E;
}
if (isupper(*str))
{
if (!strncmp(str, "SIN", 3) && !isalnum(str[3]))
{
return SIN;
}
if (!strncmp(str, "COS", 3) && !isalnum(str[3]))
{
return COS;
}
if (!strncmp(str, "TAN", 3) && !isalnum(str[3]))
{
return TAN;
}
if (!strncmp(str, "LN", 2) && !isalnum(str[2]))
{
return LN;
}
if (!strncmp(str, "POW", 3) && !isalnum(str[3]))
{
return POW;
}
if (!strncmp(str, "PI", 2) && !isalnum(str[2]))
{
return PI;
}
if (!strncmp(str, "SQRT", 4) && !isalnum(str[4]))
{
return SQRT;
}
if (!strncmp(str, "PRINT", 5) && !isalnum(str[5]))
{
return PRINT;
}
if (!strncmp(str, "LET", 3) && !isalnum(str[3]))
{
return LET;
}
if (!strncmp(str, "DIM", 3) && !isalnum(str[3]))
{
return DIM;
}
if (!strncmp(str, "IF", 2) && !isalnum(str[2]))
{
return IF;
}
if (!strncmp(str, "THEN", 4) && !isalnum(str[4]))
{
return THEN;
}
if (!strncmp(str, "AND", 3) && !isalnum(str[3]))
{
return AND;
}
if (!strncmp(str, "OR", 2) && !isalnum(str[2]))
{
return OR;
}
if (!strncmp(str, "GOTO", 4) && !isalnum(str[4]))
{
return GOTO;
}
if (!strncmp(str, "INPUT", 5) && !isalnum(str[5]))
{
return INPUT;
}
if (!strncmp(str, "REM", 3) && !isalnum(str[3]))
{
return REM;
}
if (!strncmp(str, "FOR", 3) && !isalnum(str[3]))
{
return FOR;
}
if (!strncmp(str, "TO", 2) && !isalnum(str[2]))
{
return TO;
}
if (!strncmp(str, "NEXT", 4) && !isalnum(str[4]))
{
return NEXT;
}
if (!strncmp(str, "STEP", 4) && !isalnum(str[4]))
{
return STEP;
}
if (!strncmp(str, "MOD", 3) && !isalnum(str[3]))
{
return MOD;
}
if (!strncmp(str, "ABS", 3) && !isalnum(str[3]))
{
return ABS;
}
if (!strncmp(str, "LEN", 3) && !isalnum(str[3]))
{
return LEN;
}
if (!strncmp(str, "ASCII", 5) && !isalnum(str[5]))
{
return ASCII;
}
if (!strncmp(str, "ASIN", 4) && !isalnum(str[4]))
{
return ASIN;
}
if (!strncmp(str, "ACOS", 4) && !isalnum(str[4]))
{
return ACOS;
}
if (!strncmp(str, "ATAN", 4) && !isalnum(str[4]))
{
return ATAN;
}
if (!strncmp(str, "INT", 3) && !isalnum(str[3]))
{
return INT;
}
if (!strncmp(str, "RND", 3) && !isalnum(str[3]))
{
return RND;
}
if (!strncmp(str, "VAL", 3) && !isalnum(str[3]))
{
return VAL;
}
if (!strncmp(str, "VALLEN", 6) && !isalnum(str[6]))
{
return VALLEN;
}
if (!strncmp(str, "INSTR", 5) && !isalnum(str[5]))
{
return INSTR;
}
if (!strncmp(str, "CHR$", 4))
{
return CHRSTRING;
}
if (!strncmp(str, "STR$", 4))
{
return STRSTRING;
}
if (!strncmp(str, "LEFT$", 5))
{
return LEFTSTRING;
}
if (!strncmp(str, "RIGHT$", 6))
{
return RIGHTSTRING;
}
if (!strncmp(str, "MID$", 4))
{
return MIDSTRING;
}
if (!strncmp(str, "STRING$", 7))
{
return STRINGSTRING;
}
}
/* end isupper() */
if (isalpha(*str))
{
while (isalnum(*str))
{
str++;
}
switch (*str)
{
case '$':
return str[1] == '(' ? DIMSTRID : STRID;
case '(':
return DIMFLTID;
default:
return FLTID;
}
}
return SYNTAX_ERROR;
}
}
/****************************************************************************
* Name: tokenlen
*
* Description:
* Get the length of a token.
* Params: str - pointer to the string containing the token
* token - the type of the token read
* Returns: length of the token, or 0 for EOL to prevent
* it being read past.
*
****************************************************************************/
static int tokenlen(FAR const char *str, int tokenid)
{
int len = 0;
switch (tokenid)
{
case EOS:
return 0;
case EOL:
return 1;
case VALUE:
getvalue(str, &len);
return len;
case DIMSTRID:
case DIMFLTID:
case STRID:
getid(str, g_iobuffer, &len);
return len;
case FLTID:
getid(str, g_iobuffer, &len);
return len;
case PI:
return 2;
case E:
return 1;
case SIN:
return 3;
case COS:
return 3;
case TAN:
return 3;
case LN:
return 2;
case POW:
return 3;
case SQRT:
return 4;
case DIV:
return 1;
case MULT:
return 1;
case OPAREN:
return 1;
case CPAREN:
return 1;
case PLUS:
return 1;
case MINUS:
return 1;
case SHRIEK:
return 1;
case COMMA:
return 1;
case QUOTE:
return 1;
case EQUALS:
return 1;
case LESS:
return 1;
case GREATER:
return 1;
case SEMICOLON:
return 1;
case SYNTAX_ERROR:
return 0;
case PRINT:
return 5;
case LET:
return 3;
case DIM:
return 3;
case IF:
return 2;
case THEN:
return 4;
case AND:
return 3;
case OR:
return 2;
case GOTO:
return 4;
case INPUT:
return 5;
case REM:
return 3;
case FOR:
return 3;
case TO:
return 2;
case NEXT:
return 4;
case STEP:
return 4;
case MOD:
return 3;
case ABS:
return 3;
case LEN:
return 3;
case ASCII:
return 5;
case ASIN:
return 4;
case ACOS:
return 4;
case ATAN:
return 4;
case INT:
return 3;
case RND:
return 3;
case VAL:
return 3;
case VALLEN:
return 6;
case INSTR:
return 5;
case CHRSTRING:
return 4;
case STRSTRING:
return 4;
case LEFTSTRING:
return 5;
case RIGHTSTRING:
return 6;
case MIDSTRING:
return 4;
case STRINGSTRING:
return 7;
default:
assert(0);
return 0;
}
}
/****************************************************************************
* Name: isstring
*
* Description:
* Test if a token represents a string expression
* Params: token - token to test
* Returns: 1 if a string, else 0
*
****************************************************************************/
static int isstring(int tokenid)
{
if (tokenid == STRID || tokenid == QUOTE || tokenid == DIMSTRID
|| tokenid == CHRSTRING || tokenid == STRSTRING
|| tokenid == LEFTSTRING || tokenid == RIGHTSTRING
|| tokenid == MIDSTRING || tokenid == STRINGSTRING)
{
return 1;
}
return 0;
}
/****************************************************************************
* Name: getvalue
*
* Description:
* Get a numerical value from the parse string
* Params: str - the string to search
* len - return pinter for no chars read
* Returns: the value of the string.
*
****************************************************************************/
static double getvalue(FAR const char *str, FAR int *len)
{
double answer;
FAR char *end;
answer = strtod(str, &end);
assert(end != str);
*len = end - str;
return answer;
}
/****************************************************************************
* Name: getid
*
* Description:
* Get an id from the parse string:
* Params: str - string to search
* out - id output [32 chars max ]
* len - return pointer for id length
* Notes: triggers an error if id > 31 chars
* the id includes the $ and ( qualifiers.
*
****************************************************************************/
static void getid(FAR const char *str, FAR char *out, FAR int *len)
{
int nread = 0;
while (isspace(*str))
{
str++;
}
assert(isalpha(*str));
while (isalnum(*str))
{
if (nread < 31)
{
out[nread++] = *str++;
}
else
{
seterror(ERR_IDTOOLONG);
break;
}
}
if (*str == '$')
{
if (nread < 31)
{
out[nread++] = *str++;
}
else
{
seterror(ERR_IDTOOLONG);
}
}
if (*str == '(')
{
if (nread < 31)
{
out[nread++] = *str++;
}
else
{
seterror(ERR_IDTOOLONG);
}
}
out[nread] = 0;
*len = nread;
}
/****************************************************************************
* Name: mystrgrablit
*
* Description:
* Grab a literal from the parse string.
* Params: dest - destination string
* src - source string
* Notes: strings are in quotes, double quotes the escape
*
****************************************************************************/
static void mystrgrablit(FAR char *dest, FAR const char *src)
{
assert(*src == '"');
src++;
while (*src)
{
if (*src == '"')
{
if (src[1] == '"')
{
*dest++ = *src;
src++;
src++;
}
else
{
break;
}
}
else
{
*dest++ = *src++;
}
}
*dest++ = 0;
}
/****************************************************************************
* Name: mystrend
*
* Description:
* Find where a source string literal ends
* Params: src - string to check (must point to quote)
* quote - character to use for quotation
* Returns: pointer to quote which ends string
* Notes: quotes escape quotes
*
****************************************************************************/
static FAR char *mystrend(FAR const char *str, char quote)
{
assert(*str == quote);
str++;
while (*str)
{
while (*str != quote)
{
if (*str == '\n' || *str == 0)
{
return 0;
}
str++;
}
if (str[1] == quote)
{
str += 2;
}
else
{
break;
}
}
return (char *)(*str ? str : 0);
}
/****************************************************************************
* Name: mystrcount
*
* Description:
* Count the instances of ch in str
* Params: str - string to check
* ch - character to count
* Returns: no time chs occurs in str.
*
****************************************************************************/
static int mystrcount(FAR const char *str, char ch)
{
int answer = 0;
while (*str)
{
if (*str++ == ch)
{
answer++;
}
}
return answer;
}
/****************************************************************************
* Name: mystrdup
*
* Description:
* Duplicate a string:
* Params: str - string to duplicate
* Returns: malloced duplicate.
*
****************************************************************************/
static FAR char *mystrdup(FAR const char *str)
{
return strdup(str);
}
/****************************************************************************
* Name: mystrconcat
*
* Description:
* Concatenate two strings
* Params: str - firsts string
* cat - second string
* Returns: malloced string.
*
****************************************************************************/
static FAR char *mystrconcat(FAR const char *str, FAR const char *cat)
{
int len;
FAR char *answer;
len = strlen(str) + strlen(cat) + 1;
answer = malloc(len);
if (answer)
{
strlcpy(answer, str, len);
strlcat(answer, cat, len);
}
return answer;
}
/****************************************************************************
* Name: factorial
*
* Description:
* Compute x!
*
****************************************************************************/
static double factorial(double x)
{
double answer = 1.0;
double t;
if (x > 1000.0)
{
x = 1000.0;
}
for (t = 1; t <= x; t += 1.0)
{
answer *= t;
}
return answer;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: basic
*
* Description:
* Interpret a BASIC script
*
* Input Parameters:
* script - the script to run
* in - input stream
* out - output stream
* err - error stream
*
* Returned Value:
* Returns: 0 on success, 1 on error condition.
*
****************************************************************************/
int basic(FAR const char *script, FILE * in, FILE * out, FILE * err)
{
int curline = 0;
int nextline;
int answer = 0;
g_fpin = in;
g_fpout = out;
g_fperr = err;
if (setup(script) == -1)
{
return 1;
}
while (curline != -1)
{
g_string = g_lines[curline].str;
g_token = gettoken(g_string);
g_errorflag = 0;
nextline = line();
if (g_errorflag)
{
reporterror(g_lines[curline].no);
answer = 1;
break;
}
if (nextline == -1)
{
break;
}
if (nextline == 0)
{
curline++;
if (curline == nlines)
break;
}
else
{
curline = findline(nextline);
if (curline == -1)
{
if (g_fperr)
{
fprintf(g_fperr, "line %d not found\n", nextline);
}
answer = 1;
break;
}
}
}
cleanup();
return answer;
}