HTRACE-386. htrace-c: add functions for retrieving the span ID to the public API. (Colin Patrick McCabe via iwasakims)
diff --git a/htrace-c/src/core/htrace.h b/htrace-c/src/core/htrace.h
index 03c02bb..7357d4c 100644
--- a/htrace-c/src/core/htrace.h
+++ b/htrace-c/src/core/htrace.h
@@ -20,6 +20,7 @@
#define APACHE_HTRACE_HTRACE_H
#include <stdint.h> /* for uint64_t, etc. */
+#include <unistd.h> /* for size_t, etc. */
/**
* The public API for the HTrace C client.
@@ -169,6 +170,11 @@
*/
#define HTRACE_PROB_SAMPLER_FRACTION_KEY "prob.sampler.fraction"
+/**
+ * The length of an HTrace span ID in hexadecimal string form.
+ */
+#define HTRACE_SPAN_ID_STRING_LENGTH 32
+
// Forward declarations
struct htrace_conf;
struct htracer;
@@ -342,6 +348,83 @@
*/
void htrace_scope_close(struct htrace_scope *scope);
+ /**
+ * The HTrace span id.
+ */
+ struct htrace_span_id {
+ uint64_t high;
+ uint64_t low;
+ };
+
+ /**
+ * Set a span ID to the invalid span ID by clearing it.
+ *
+ * @param id The span ID to clear.
+ */
+ void htrace_span_id_clear(struct htrace_span_id *id);
+
+ /**
+ * Compare two span IDs.
+ *
+ * @param a The first span ID.
+ * @param b The second span ID.
+ *
+ * @return A number less than 0 if the first span ID is less;
+ * A number greater than 0 if the first span ID is greater;
+ * 0 if the span IDs are equal.
+ */
+ int htrace_span_id_compare(const struct htrace_span_id *a,
+ const struct htrace_span_id *b);
+
+ /**
+ * Parse a string containing an HTrace span ID.
+ *
+ * @param id The HTrace span ID to fill in.
+ * @param str The string to parse.
+ * @param err (out parameter) a buffer into which we will
+ * write an error message, if parsing fails.
+ * If this is unchanged, there was no error.
+ * @param err_len The length of the err buffer.
+ *
+ */
+ void htrace_span_id_parse(struct htrace_span_id *id, const char *str,
+ char *err, size_t err_len);
+
+ /**
+ * Write an HTrace span ID to a string.
+ *
+ * @param id The HTrace span ID.
+ * @param str Where to put the string.
+ * @param len The length of the string buffer.
+ *
+ * @return 1 on success; 0 if the length was not long enough, or
+ * there was an internal snprintf error.
+ */
+ int htrace_span_id_to_str(const struct htrace_span_id *id,
+ char *str, size_t len);
+
+ /**
+ * Copy an htrace span ID.
+ *
+ * dst and src can be the same.
+ *
+ * @param dst The destination span ID.
+ * @param src The source span ID.
+ */
+ void htrace_span_id_copy(struct htrace_span_id *dst,
+ const struct htrace_span_id *src);
+
+ /**
+ * Get the span id of an HTrace scope.
+ *
+ * @param scope The trace scope, or NULL.
+ * @param id (out param) The htrace span ID object to modify.
+ * It will be set to the invalid span ID if the scope
+ * is null or has no span.
+ */
+ void htrace_scope_get_span_id(const struct htrace_scope *scope,
+ struct htrace_span_id *id);
+
#pragma GCC visibility pop // End publicly visible symbols
#ifdef __cplusplus
diff --git a/htrace-c/src/core/htrace.hpp b/htrace-c/src/core/htrace.hpp
index 0378c57..6f6a398 100644
--- a/htrace-c/src/core/htrace.hpp
+++ b/htrace-c/src/core/htrace.hpp
@@ -49,6 +49,109 @@
class Scope;
class Tracer;
+ class SpanId {
+ public:
+ SpanId() {
+ id_.low = 0;
+ id_.high = 0;
+ }
+
+ SpanId(uint64_t high, uint64_t low) {
+ id_.high = high;
+ id_.low = low;
+ }
+
+ SpanId(const struct htrace_span_id *other) {
+ id_.high = other->high;
+ id_.low = other->low;
+ }
+
+ SpanId(const SpanId &other) {
+ id_.high = other.id_.high;
+ id_.low = other.id_.low;
+ }
+
+ /**
+ * Convert an input string into a span id.
+ *
+ * @param input The input string.
+ *
+ * @return The empty string, if parsing was successful. A
+ * failure error message, if parsing failed.
+ * If parsing is successful the current ID object
+ * will be modified.
+ */
+ std::string FromString(const std::string &input) {
+ char err[512];
+ err[0] = '\0';
+ htrace_span_id_parse(&id_, input.c_str(), err, sizeof(err));
+ if (err[0]) {
+ return std::string(err);
+ }
+ return "";
+ }
+
+ SpanId &operator=(const SpanId &other) {
+ id_.high = other.id_.high;
+ id_.low = other.id_.low;
+ return *this;
+ }
+
+ bool operator<(const SpanId &other) const {
+ return (htrace_span_id_compare(&id_, &other.id_) < 0);
+ }
+
+ bool operator==(const SpanId &other) const {
+ return ((id_.high == other.id_.high) &&
+ (id_.low == other.id_.low));
+ }
+
+ bool operator!=(const SpanId &other) const {
+ return (!((*this) == other));
+ }
+
+ uint64_t GetHigh() {
+ return id_.high;
+ }
+
+ void SetHigh(uint64_t high) {
+ id_.high = high;
+ }
+
+ uint64_t GetLow() {
+ return id_.low;
+ }
+
+ void SetLow(uint64_t low) {
+ id_.low = low;
+ }
+
+ void Clear() {
+ htrace_span_id_clear(&id_);
+ }
+
+ /**
+ * Convert the SpanId to a human-readable string.
+ */
+ std::string ToString() const {
+ char str[HTRACE_SPAN_ID_STRING_LENGTH + 1];
+ if (!htrace_span_id_to_str(&id_, str, sizeof(str))) {
+ // This should not happen, because the buffer we supplied is long
+ // enough.
+ return "(error converting ID to string)";
+ }
+ return std::string(str);
+ }
+
+ private:
+ struct htrace_span_id id_;
+ };
+
+ std::ostream &operator<<(std::ostream &oss, const SpanId &spanId) {
+ oss << spanId.ToString();
+ return oss;
+ }
+
/**
* An HTrace Configuration object.
*
@@ -221,6 +324,12 @@
scope_ = NULL;
}
+ SpanId GetSpanId() const {
+ htrace_span_id id;
+ htrace_scope_get_span_id(scope_, &id);
+ return SpanId(&id);
+ }
+
private:
friend class Tracer;
Scope(htrace::Scope &other); // Can't copy
diff --git a/htrace-c/src/core/scope.h b/htrace-c/src/core/scope.h
index 9f00b13..6d914b7 100644
--- a/htrace-c/src/core/scope.h
+++ b/htrace-c/src/core/scope.h
@@ -55,17 +55,6 @@
struct htrace_span *span;
};
-/**
- * Get the span id of an HTrace scope.
- *
- * @param scope The trace scope, or NULL.
- * @param id (out param) The htrace span ID object to modify.
- * It will be set to the invalid span ID if the scope
- * is null or has no span.
- */
-void htrace_scope_get_span_id(const struct htrace_scope *scope,
- struct htrace_span_id *id);
-
#endif
// vim: ts=4:sw=4:et
diff --git a/htrace-c/src/core/span.c b/htrace-c/src/core/span.c
index 44f4e6c..b7ca87a 100644
--- a/htrace-c/src/core/span.c
+++ b/htrace-c/src/core/span.c
@@ -16,6 +16,7 @@
* limitations under the License.
*/
+#include "core/htrace.h"
#include "core/span.h"
#include "receiver/receiver.h"
#include "sampler/sampler.h"
diff --git a/htrace-c/src/core/span.h b/htrace-c/src/core/span.h
index d6fbeb5..b3a79a0 100644
--- a/htrace-c/src/core/span.h
+++ b/htrace-c/src/core/span.h
@@ -27,6 +27,7 @@
* This is an internal header, not intended for external use.
*/
+#include "core/htrace.h" /* for struct span_id */
#include "core/span_id.h"
#include <stdint.h>
diff --git a/htrace-c/src/core/span_id.c b/htrace-c/src/core/span_id.c
index 7ea23eb..9c4acae 100644
--- a/htrace-c/src/core/span_id.c
+++ b/htrace-c/src/core/span_id.c
@@ -16,6 +16,7 @@
* limitations under the License.
*/
+#include "core/htrace.h"
#include "core/span_id.h"
#include "util/cmp.h"
#include "util/log.h"
diff --git a/htrace-c/src/core/span_id.h b/htrace-c/src/core/span_id.h
index af2e725..8f21bda 100644
--- a/htrace-c/src/core/span_id.h
+++ b/htrace-c/src/core/span_id.h
@@ -34,11 +34,6 @@
struct random_src;
/**
- * Length of an HTrace span ID in hexadecimal string form.
- */
-#define HTRACE_SPAN_ID_STRING_LENGTH 32
-
-/**
* The number of bytes in the HTrace span ID
*/
#define HTRACE_SPAN_ID_NUM_BYTES 16
@@ -49,50 +44,6 @@
extern const struct htrace_span_id INVALID_SPAN_ID;
/**
- * The HTrace span id.
- */
-struct htrace_span_id {
- uint64_t high;
- uint64_t low;
-};
-
-/**
- * Parse a string containing an HTrace span ID.
- *
- * @param id The HTrace span ID to fill in.
- * @param str The string to parse.
- *
- */
-void htrace_span_id_parse(struct htrace_span_id *id, const char *str,
- char *err, size_t err_len);
-
-/**
- * Write an HTrace span ID to a string.
- *
- * @param id The HTrace span ID.
- * @param str Where to put the string.
- * @param len The length of the string buffer.
- * @param err The error buffer to be set on failure.
- * @param err_len Length of the error buffer.
- *
- * @return 1 on success; 0 if the length was not long enough, or
- * there was an internal snprintf error.
- */
-int htrace_span_id_to_str(const struct htrace_span_id *id,
- char *str, size_t len);
-
-/**
- * Copy an htrace span ID.
- *
- * dst and src can be the same.
- *
- * @param dst The destination span ID.
- * @param src The source span ID.
- */
-void htrace_span_id_copy(struct htrace_span_id *dst,
- const struct htrace_span_id *src);
-
-/**
* Write this span ID to the provided CMP context.
*
* @param span The span.
@@ -124,26 +75,6 @@
void htrace_span_id_generate(struct htrace_span_id *id, struct random_src *rnd,
const struct htrace_span_id *parent);
-/**
- * Set a span ID to the invalid span ID by clearing it.
- *
- * @param id The span ID to clear.
- */
-void htrace_span_id_clear(struct htrace_span_id *id);
-
-/**
- * Compare two span IDs.
- *
- * @param a The first span ID.
- * @param b The second span ID.
- *
- * @return A number less than 0 if the first span ID is less;
- * A number greater than 0 if the first span ID is greater;
- * 0 if the span IDs are equal.
- */
-int htrace_span_id_compare(const struct htrace_span_id *a,
- const struct htrace_span_id *b);
-
#endif
// vim: ts=4:sw=4:et
diff --git a/htrace-c/src/test/linkage-unit.c b/htrace-c/src/test/linkage-unit.c
index bba73e1..f3e4caf 100644
--- a/htrace-c/src/test/linkage-unit.c
+++ b/htrace-c/src/test/linkage-unit.c
@@ -48,7 +48,13 @@
"htrace_start_span",
"htracer_create",
"htracer_free",
- "htracer_tname"
+ "htracer_tname",
+ "htrace_span_id_clear",
+ "htrace_span_id_compare",
+ "htrace_span_id_parse",
+ "htrace_span_id_to_str",
+ "htrace_span_id_copy",
+ "htrace_scope_get_span_id",
};
#define PUBLIC_SYMS_SIZE (sizeof(PUBLIC_SYMS) / sizeof(PUBLIC_SYMS[0]))
diff --git a/htrace-c/src/test/span_id-unit.c b/htrace-c/src/test/span_id-unit.c
index 06c0320..ecdebfb 100644
--- a/htrace-c/src/test/span_id-unit.c
+++ b/htrace-c/src/test/span_id-unit.c
@@ -16,6 +16,7 @@
* limitations under the License.
*/
+#include "core/htrace.h"
#include "core/span_id.h"
#include "test/span_util.h"
#include "test/test.h"
