Starting with a change to ensure that ast_verbose() preserves ABI compatibility

in 1.6.1 (as compared to 1.6.0 and versions of 1.4), this change also
deprecates the use of Asterisk with FreeBSD 4, given the central use of va_copy
in core functions.  va_copy() is C99, anyway, and we already require C99 for
other purposes, so this isn't really a big change anyway.  This change also
simplifies some of the core ast_str_* functions.


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@157639 65c4cc65-6c06-0410-ace0-fbb531ad65f3

include/asterisk/logger.h

@@ -80,6 +80,10 @@ void __ast_verbose(const char *file, int line, const char *func, const char *fmt
 
 #define ast_verbose(...) __ast_verbose(__FILE__, __LINE__, __PRETTY_FUNCTION__,  __VA_ARGS__)
 
+void __ast_verbose_ap(const char *file, int line, const char *func, const char *fmt, va_list ap);
+
+#define ast_verbose_ap(fmt, ap)	__ast_verbose_ap(__FILE__, __LINE__, __PRETTY_FUNCTION__, fmt, ap)
+
 void ast_child_verbose(int level, const char *fmt, ...)
 	__attribute__ ((format (printf, 2, 3)));
 

include/asterisk/strings.h

@@ -425,15 +425,17 @@ void ast_str_trim_blanks(struct ast_str *buf),
 AST_INLINE_API(
 int _ast_str_make_space(struct ast_str **buf, size_t new_len, const char *file, int lineno, const char *function),
 {
-	_DB1(struct ast_str *old_buf = *buf;)
+	struct ast_str *old_buf = *buf;
 
 	if (new_len <= (*buf)->len) 
 		return 0;	/* success */
 	if ((*buf)->ts == DS_ALLOCA || (*buf)->ts == DS_STATIC)
 		return -1;	/* cannot extend */
 	*buf = (struct ast_str *)__ast_realloc(*buf, new_len + sizeof(struct ast_str), file, lineno, function);
-	if (*buf == NULL) /* XXX watch out, we leak memory here */
+	if (*buf == NULL) {
+		*buf = old_buf;
 		return -1;
+	}
 	if ((*buf)->ts != DS_MALLOC) {
 		pthread_setspecific((*buf)->ts->key, *buf);
 		_DB1(__ast_threadstorage_object_replace(old_buf, *buf, new_len + sizeof(struct ast_str));)
@@ -448,15 +450,17 @@ int _ast_str_make_space(struct ast_str **buf, size_t new_len, const char *file,
 AST_INLINE_API(
 int ast_str_make_space(struct ast_str **buf, size_t new_len),
 {
-	_DB1(struct ast_str *old_buf = *buf;)
+	struct ast_str *old_buf = *buf;
 
 	if (new_len <= (*buf)->len) 
 		return 0;	/* success */
 	if ((*buf)->ts == DS_ALLOCA || (*buf)->ts == DS_STATIC)
 		return -1;	/* cannot extend */
 	*buf = (struct ast_str *)ast_realloc(*buf, new_len + sizeof(struct ast_str));
-	if (*buf == NULL) /* XXX watch out, we leak memory here */
+	if (*buf == NULL) {
+		*buf = old_buf;
 		return -1;
+	}
 	if ((*buf)->ts != DS_MALLOC) {
 		pthread_setspecific((*buf)->ts->key, *buf);
 		_DB1(__ast_threadstorage_object_replace(old_buf, *buf, new_len + sizeof(struct ast_str));)
@@ -557,12 +561,8 @@ struct ast_str *__ast_str_thread_get(struct ast_threadstorage *ts,
 /*!
  * \brief Error codes from __ast_str_helper()
  * The undelying processing to manipulate dynamic string is done
- * by __ast_str_helper(), which can return a success, a
- * permanent failure (e.g. no memory), or a temporary one (when
- * the string needs to be reallocated, and we must run va_start()
- * again; XXX this convoluted interface is only here because
- * FreeBSD 4 lacks va_copy, but this will be fixed and the
- * interface simplified).
+ * by __ast_str_helper(), which can return a success or a
+ * permanent failure (e.g. no memory).
  */
 enum {
 	/*! An error has occurred and the contents of the dynamic string
@@ -570,11 +570,36 @@ enum {
 	AST_DYNSTR_BUILD_FAILED = -1,
 	/*! The buffer size for the dynamic string had to be increased, and
 	 *  __ast_str_helper() needs to be called again after
-	 *  a va_end() and va_start().
+	 *  a va_end() and va_start().  This return value is legacy and will
+	 *  no longer be used.
 	 */
 	AST_DYNSTR_BUILD_RETRY = -2
 };
 
+/*!
+ * \brief Core functionality of ast_str_(set|append)_va
+ *
+ * The arguments to this function are the same as those described for
+ * ast_str_set_va except for an addition argument, append.
+ * If append is non-zero, this will append to the current string instead of
+ * writing over it.
+ *
+ * AST_DYNSTR_BUILD_RETRY is a legacy define.  It should probably never
+ * again be used.
+ *
+ * A return of AST_DYNSTR_BUILD_FAILED indicates a memory allocation error.
+ *
+ * A return value greater than or equal to zero indicates the number of
+ * characters that have been written, not including the terminating '\0'.
+ * In the append case, this only includes the number of characters appended.
+ *
+ * \note This function should never need to be called directly.  It should
+ *       through calling one of the other functions or macros defined in this
+ *       file.
+ */
+int __ast_str_helper(struct ast_str **buf, size_t max_len,
+	int append, const char *fmt, va_list ap);
+
 /*!
  * \brief Set a dynamic string from a va_list
  *
@@ -612,62 +637,23 @@ enum {
  *      ...
  * }
  * \endcode
- *
- * \note: the following two functions must be implemented as macros
- *	because we must do va_end()/va_start() on the original arguments.
  */
-#define ast_str_set_va(buf, max_len, fmt, ap)			\
-	({								\
-		int __res;						\
-		while ((__res = __ast_str_helper(buf, max_len,		\
-			0, fmt, ap)) == AST_DYNSTR_BUILD_RETRY) {	\
-			va_end(ap);					\
-			va_start(ap, fmt);				\
-		}							\
-		(__res);						\
-	})
+AST_INLINE_API(int ast_str_set_va(struct ast_str **buf, size_t max_len, const char *fmt, va_list ap),
+{
+	return __ast_str_helper(buf, max_len, 0, fmt, ap);
+}
+)
 
 /*!
  * \brief Append to a dynamic string using a va_list
  *
  * Same as ast_str_set_va(), but append to the current content.
  */
-#define ast_str_append_va(buf, max_len, fmt, ap)		\
-	({								\
-		int __res;						\
-		while ((__res = __ast_str_helper(buf, max_len,		\
-			1, fmt, ap)) == AST_DYNSTR_BUILD_RETRY) {	\
-			va_end(ap);					\
-			va_start(ap, fmt);				\
-		}							\
-		(__res);						\
-	})
-
-/*!
- * \brief Core functionality of ast_str_(set|append)_va
- *
- * The arguments to this function are the same as those described for
- * ast_str_set_va except for an addition argument, append.
- * If append is non-zero, this will append to the current string instead of
- * writing over it.
- *
- * In the case that this function is called and the buffer was not large enough
- * to hold the result, the partial write will be truncated, and the result
- * AST_DYNSTR_BUILD_RETRY will be returned to indicate that the buffer size
- * was increased, and the function should be called a second time.
- *
- * A return of AST_DYNSTR_BUILD_FAILED indicates a memory allocation error.
- *
- * A return value greater than or equal to zero indicates the number of
- * characters that have been written, not including the terminating '\0'.
- * In the append case, this only includes the number of characters appended.
- *
- * \note This function should never need to be called directly.  It should
- *       through calling one of the other functions or macros defined in this
- *       file.
- */
-int __ast_str_helper(struct ast_str **buf, size_t max_len,
-	int append, const char *fmt, va_list ap);
+AST_INLINE_API(int ast_str_append_va(struct ast_str **buf, size_t max_len, const char *fmt, va_list ap),
+{
+	return __ast_str_helper(buf, max_len, 1, fmt, ap);
+}
+)
 
 /*!
  * \brief Set a dynamic string using variable arguments

main/logger.c

@@ -1232,12 +1232,11 @@ void ast_backtrace(void)
 #endif
 }
 
-void __ast_verbose(const char *file, int line, const char *func, const char *fmt, ...)
+void __ast_verbose_ap(const char *file, int line, const char *func, const char *fmt, va_list ap)
 {
 	struct logmsg *logmsg = NULL;
 	struct ast_str *buf = NULL;
 	int res = 0;
-	va_list ap;
 
 	if (!(buf = ast_str_thread_get(&verbose_buf, VERBOSE_BUF_INIT_SIZE)))
 		return;
@@ -1261,9 +1260,7 @@ void __ast_verbose(const char *file, int line, const char *func, const char *fmt
 	}
 
 	/* Build string */
-	va_start(ap, fmt);
 	res = ast_str_set_va(&buf, 0, fmt, ap);
-	va_end(ap);
 
 	/* If the build failed then we can drop this allocated message */
 	if (res == AST_DYNSTR_BUILD_FAILED)
@@ -1291,6 +1288,25 @@ void __ast_verbose(const char *file, int line, const char *func, const char *fmt
 	}
 }
 
+void __ast_verbose(const char *file, int line, const char *func, const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	__ast_verbose_ap(file, line, func, fmt, ap);
+	va_end(ap);
+}
+
+/* No new code should use this directly, but we have the ABI for backwards compat */
+#undef ast_verbose
+void ast_verbose(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
+void ast_verbose(const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	__ast_verbose_ap("", 0, "", fmt, ap);
+	va_end(ap);
+}
+
 int ast_register_verbose(void (*v)(const char *string)) 
 {
 	struct verb *verb;

main/utils.c

@@ -1667,37 +1667,45 @@ int __ast_str_helper(struct ast_str **buf, size_t max_len,
 {
 	int res, need;
 	int offset = (append && (*buf)->len) ? (*buf)->used : 0;
+	va_list aq;
 
-	if (max_len < 0)
-		max_len = (*buf)->len;	/* don't exceed the allocated space */
-	/*
-	 * Ask vsnprintf how much space we need. Remember that vsnprintf
-	 * does not count the final '\0' so we must add 1.
-	 */
-	res = vsnprintf((*buf)->str + offset, (*buf)->len - offset, fmt, ap);
-
-	need = res + offset + 1;
-	/*
-	 * If there is not enough space and we are below the max length,
-	 * reallocate the buffer and return a message telling to retry.
-	 */
-	if (need > (*buf)->len && (max_len == 0 || (*buf)->len < max_len) ) {
-		if (max_len && max_len < need)	/* truncate as needed */
-			need = max_len;
-		else if (max_len == 0)	/* if unbounded, give more room for next time */
-			need += 16 + need/4;
-		if (0)	/* debugging */
-			ast_verbose("extend from %d to %d\n", (int)(*buf)->len, need);
-		if (ast_str_make_space(buf, need)) {
-			ast_verbose("failed to extend from %d to %d\n", (int)(*buf)->len, need);
-			return AST_DYNSTR_BUILD_FAILED;
+	do {
+		if (max_len < 0) {
+			max_len = (*buf)->len;	/* don't exceed the allocated space */
 		}
-		(*buf)->str[offset] = '\0';	/* Truncate the partial write. */
+		/*
+		 * Ask vsnprintf how much space we need. Remember that vsnprintf
+		 * does not count the final '\0' so we must add 1.
+		 */
+		va_copy(aq, ap);
+		res = vsnprintf((*buf)->str + offset, (*buf)->len - offset, fmt, aq);
 
-		/* va_end() and va_start() must be done before calling
-		 * vsnprintf() again. */
-		return AST_DYNSTR_BUILD_RETRY;
-	}
+		need = res + offset + 1;
+		/*
+		 * If there is not enough space and we are below the max length,
+		 * reallocate the buffer and return a message telling to retry.
+		 */
+		if (need > (*buf)->len && (max_len == 0 || (*buf)->len < max_len) ) {
+			if (max_len && max_len < need) {	/* truncate as needed */
+				need = max_len;
+			} else if (max_len == 0) {	/* if unbounded, give more room for next time */
+				need += 16 + need / 4;
+			}
+			if (0) {	/* debugging */
+				ast_verbose("extend from %d to %d\n", (int)(*buf)->len, need);
+			}
+			if (ast_str_make_space(buf, need)) {
+				ast_verbose("failed to extend from %d to %d\n", (int)(*buf)->len, need);
+				return AST_DYNSTR_BUILD_FAILED;
+			}
+			(*buf)->str[offset] = '\0';	/* Truncate the partial write. */
+
+			/* Restart va_copy before calling vsnprintf() again. */
+			va_end(aq);
+			continue;
+		}
+		break;
+	} while (1);
 	/* update space used, keep in mind the truncation */
 	(*buf)->used = (res + offset > (*buf)->len) ? (*buf)->len : res + offset;