| /**************************************************************************** |
| * env_getenv.c |
| * |
| * Copyright (C) 2007, 2008 Gregory Nutt. All rights reserved. |
| * Author: Gregory Nutt <spudmonkey@racsa.co.cr> |
| * |
| * 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 <nuttx/config.h> |
| |
| #ifndef CONFIG_DISABLE_ENVIRON |
| |
| #include <sched.h> |
| #include <string.h> |
| #include <stdlib.h> |
| #include <errno.h> |
| |
| #include "os_internal.h" |
| #include "env_internal.h" |
| |
| /**************************************************************************** |
| * Private Data |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Public Functions |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Function: getenv |
| * |
| * Description: |
| * The getenv() function searches the environment list for a string that |
| * matches the string pointed to by name. |
| * |
| * Parameters: |
| * name - The name of the variable to find. |
| * |
| * Return Value: |
| * The value of the valiable (read-only) or NULL on failure |
| * |
| * Assumptions: |
| * Not called from an interrupt handler |
| * |
| ****************************************************************************/ |
| |
| FAR char *getenv(const char *name) |
| { |
| FAR _TCB *rtcb; |
| FAR environ_t *envp; |
| FAR char *pvar; |
| FAR char *pvalue = NULL; |
| int ret = OK; |
| |
| /* Verify that a string was passed */ |
| |
| if (!name) |
| { |
| ret = EINVAL; |
| goto errout; |
| } |
| |
| |
| /* Get a reference to the thread-private environ in the TCB.*/ |
| |
| sched_lock(); |
| rtcb = (FAR _TCB*)g_readytorun.head; |
| envp = rtcb->envp; |
| |
| /* Check if the variable exists */ |
| |
| if ( !envp || (pvar = env_findvar(envp, name)) == NULL) |
| { |
| ret = ENOENT; |
| goto errout_with_lock; |
| } |
| |
| /* It does! Get the value sub-string from the name=value string */ |
| |
| pvalue = strchr(pvar, '='); |
| if (!pvalue) |
| { |
| /* The name=value string has no '=' This is a bug! */ |
| |
| ret = EINVAL; |
| goto errout_with_lock; |
| } |
| |
| /* Adjust the pointer so that it points to the value right after the '=' */ |
| |
| pvalue++; |
| sched_unlock(); |
| return pvalue; |
| |
| errout_with_lock: |
| sched_unlock(); |
| errout: |
| *get_errno_ptr() = ret; |
| return NULL; |
| } |
| |
| #endif /* CONFIG_DISABLE_ENVIRON */ |
| |
| |
| |