[asterisk-commits] rizzo: trunk r48509 - in /trunk: include/asterisk/ main/

asterisk-commits at lists.digium.com asterisk-commits at lists.digium.com
Fri Dec 15 15:08:46 MST 2006


Author: rizzo
Date: Fri Dec 15 16:08:46 2006
New Revision: 48509

URL: http://svn.digium.com/view/asterisk?view=rev&rev=48509
Log:
move the dynamic string support in a better place i.e. string.h

While doing this, add a bit of documentation, and slightly
extend the functionality as follows:
 + a max_len of -1 means that we take whatever the current size
   is, and never try to extend the buffer;
 + add support for alloca()-ted dynamic strings, which is very
   useful for all cases where we do an ast_build_string() now.

Next step is to simplify the interface by using shorter names
(e.g. ast_str as a prefix) and removing the _thread variant
of the functions by saving the threadstorage reference into
the struct ast_str. This can be done by overloading the
'type' field.

Finally, I will do my best to remove the convoluted interface
that results from trying to support platforms without va_copy().


Modified:
    trunk/include/asterisk/strings.h
    trunk/include/asterisk/threadstorage.h
    trunk/include/asterisk/utils.h
    trunk/main/utils.c

Modified: trunk/include/asterisk/strings.h
URL: http://svn.digium.com/view/asterisk/trunk/include/asterisk/strings.h?view=diff&rev=48509&r1=48508&r2=48509
==============================================================================
--- trunk/include/asterisk/strings.h (original)
+++ trunk/include/asterisk/strings.h Fri Dec 15 16:08:46 2006
@@ -29,6 +29,8 @@
 #include "asterisk/inline_api.h"
 #include "asterisk/compiler.h"
 #include "asterisk/compat.h"
+#include "asterisk/utils.h"
+#include "asterisk/threadstorage.h"
 
 static force_inline int ast_strlen_zero(const char *s)
 {
@@ -256,4 +258,398 @@
 		(ra)->ptr; \
 	})
 
+/*!
+ * Support for dynamic strings.
+ *
+ * A dynamic string is just a C string prefixed by a few control fields
+ * that help setting/appending/extending it using a printf-like syntax.
+ *
+ * One should never declare a variable with this type, but only a pointer
+ * to it, e.g.
+ *
+ *	struct ast_dynamic_str *ds;
+ *
+ * The pointer can be initialized with the following:
+ *
+ *	ds = ast_dynamic_str_create(init_len);
+ *		creates a malloc()'ed dynamic string;
+ *
+ *	ds = ast_dynamic_str_alloca(init_len);
+ *		creates a string on the stack (not very dynamic!).
+ *
+ *	ds = ast_dynamic_str_thread_get(ts, init_len)
+ *		creates a malloc()'ed dynamic string associated to
+ *		the thread-local storage key ts
+ *
+ * Finally, the string can be manipulated with the following:
+ *
+ *	ast_dynamic_str_set(&buf, max_len, ts, fmt, ...)
+ *	ast_dynamic_str_append(&buf, max_len, ts, fmt, ...)
+ *	ast_dynamic_str_thread_set(&buf, max_len, ts, fmt, ...)
+ *	ast_dynamic_str_thread_append(&buf, max_len, ts, fmt, ...)
+ *
+ * and their varargs format.
+ *
+ * \arg max_len The maximum allowed length, reallocating if needed.
+ * 	0 means unlimited, -1 means "at most the available space"
+ *
+ * XXX the [_thread] variants can be removed if we save the ts in the
+ * string descriptor.
+ */
+
+/*! \brief type of storage used for dynamic string */
+enum dynstr_type {
+	DS_MALLOC = 1,
+	DS_ALLOCA = 2,
+	DS_STATIC = 3,	/* XXX not supported yet */
+};
+
+/*! \brief The descriptor of a dynamic string
+ *  XXX storage will be optimized later if needed
+ */
+struct ast_dynamic_str {
+	size_t len;	/*!< The current maximum length of the string */
+	size_t used;	/*!< Amount of space used */
+	enum dynstr_type type;	/*!< What kind of storage is this ? */
+	char str[0];	/*!< The string buffer */
+};
+
+/*!
+ * \brief Create a malloc'ed dynamic length string
+ *
+ * \arg init_len This is the initial length of the string buffer
+ *
+ * \return This function returns a pointer to the dynamic string length.  The
+ *         result will be NULL in the case of a memory allocation error.
+ *
+ * \note The result of this function is dynamically allocated memory, and must
+ *       be free()'d after it is no longer needed.
+ */
+AST_INLINE_API(
+struct ast_dynamic_str * attribute_malloc ast_dynamic_str_create(size_t init_len),
+{
+	struct ast_dynamic_str *buf;
+
+	if (!(buf = ast_calloc(1, sizeof(*buf) + init_len)))
+		return NULL;
+	
+	buf->len = init_len;
+	buf->used = 0;
+	buf->type = DS_MALLOC;
+
+	return buf;
+}
+)
+
+#define ast_dynamic_str_alloca(init_len)		\
+	({						\
+		struct ast_dynamic_str *buf;		\
+		buf = alloca(sizeof(*buf) + init_len);	\
+		buf->len = init_len;			\
+		buf->used = 0;				\
+		buf->type = DS_ALLOCA;			\
+		buf->str[0] = '\0';			\
+		(buf);					\
+	})
+
+
+/*!
+ * \brief Retrieve a thread locally stored dynamic string
+ *
+ * \arg ts This is a pointer to the thread storage structure declared by using
+ *      the AST_THREADSTORAGE macro.  If declared with 
+ *      AST_THREADSTORAGE(my_buf, my_buf_init), then this argument would be 
+ *      (&my_buf).
+ * \arg init_len This is the initial length of the thread's dynamic string. The
+ *      current length may be bigger if previous operations in this thread have
+ *      caused it to increase.
+ *
+ * \return This function will return the thread locally stored dynamic string
+ *         associated with the thread storage management variable passed as the
+ *         first argument.
+ *         The result will be NULL in the case of a memory allocation error.
+ *
+ * Example usage:
+ * \code
+ * AST_THREADSTORAGE(my_str, my_str_init);
+ * #define MY_STR_INIT_SIZE   128
+ * ...
+ * void my_func(const char *fmt, ...)
+ * {
+ *      struct ast_dynamic_str *buf;
+ *
+ *      if (!(buf = ast_dynamic_str_thread_get(&my_str, MY_STR_INIT_SIZE)))
+ *           return;
+ *      ...
+ * }
+ * \endcode
+ */
+AST_INLINE_API(
+struct ast_dynamic_str *ast_dynamic_str_thread_get(struct ast_threadstorage *ts,
+	size_t init_len),
+{
+	struct ast_dynamic_str *buf;
+
+	if (!(buf = ast_threadstorage_get(ts, sizeof(*buf) + init_len)))
+		return NULL;
+	
+	if (!buf->len) {
+		buf->len = init_len;
+		buf->used = 0;
+		buf->type = DS_MALLOC;
+	}
+
+	return buf;
+}
+)
+
+/*!
+ * \brief Error codes from __ast_dyn_str_helper()
+ * The undelying processing to manipulate dynamic string is done
+ * by __ast_dyn_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).
+ */
+enum {
+	/*! An error has occured and the contents of the dynamic string
+	 *  are undefined */
+	AST_DYNSTR_BUILD_FAILED = -1,
+	/*! The buffer size for the dynamic string had to be increased, and
+	 *  ast_dynamic_str_thread_build_va() needs to be called again after
+	 *  a va_end() and va_start().
+	 */
+	AST_DYNSTR_BUILD_RETRY = -2
+};
+
+/*!
+ * \brief Set a thread locally stored dynamic string from a va_list
+ *
+ * \arg buf This is the address of a pointer to an ast_dynamic_str which should
+ *      have been retrieved using ast_dynamic_str_thread_get.  It will need to
+ *      be updated in the case that the buffer has to be reallocated to
+ *      accommodate a longer string than what it currently has space for.
+ * \arg max_len This is the maximum length to allow the string buffer to grow
+ *      to.  If this is set to 0, then there is no maximum length.
+ * \arg ts This is a pointer to the thread storage structure declared by using
+ *      the AST_THREADSTORAGE macro.  If declared with 
+ *      AST_THREADSTORAGE(my_buf, my_buf_init), then this argument would be 
+ *      (&my_buf).
+ * \arg fmt This is the format string (printf style)
+ * \arg ap This is the va_list
+ *
+ * \return The return value of this function is the same as that of the printf
+ *         family of functions.
+ *
+ * Example usage:
+ * \code
+ * AST_THREADSTORAGE(my_str, my_str_init);
+ * #define MY_STR_INIT_SIZE   128
+ * ...
+ * void my_func(const char *fmt, ...)
+ * {
+ *      struct ast_dynamic_str *buf;
+ *      va_list ap;
+ *
+ *      if (!(buf = ast_dynamic_str_thread_get(&my_str, MY_STR_INIT_SIZE)))
+ *           return;
+ *      ...
+ *      va_start(fmt, ap);
+ *      ast_dynamic_str_thread_set_va(&buf, 0, &my_str, fmt, ap);
+ *      va_end(ap);
+ * 
+ *      printf("This is the string we just built: %s\n", buf->str);
+ *      ...
+ * }
+ * \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_dynamic_str_thread_set_va(buf, max_len, ts, fmt, ap)	\
+	({								\
+		int __res;						\
+		while ((__res = __ast_dyn_str_helper(buf, max_len,	\
+			ts, 0, fmt, ap)) == AST_DYNSTR_BUILD_RETRY) {	\
+			va_end(ap);					\
+			va_start(ap, fmt);				\
+		}							\
+		(__res);						\
+	})
+
+/*!
+ * \brief Append to a thread local dynamic string using a va_list
+ *
+ * The arguments, return values, and usage of this are the same as those for
+ * ast_dynamic_str_thread_set_va().  However, instead of setting a new value
+ * for the string, this will append to the current value.
+ */
+#define ast_dynamic_str_thread_append_va(buf, max_len, ts, fmt, ap)	\
+	({								\
+		int __res;						\
+		while ((__res = __ast_dyn_str_helper(buf, max_len,	\
+			ts, 1, fmt, ap)) == AST_DYNSTR_BUILD_RETRY) {	\
+			va_end(ap);					\
+			va_start(ap, fmt);				\
+		}							\
+		(__res);						\
+	})
+
+/*!
+ * \brief Core functionality of ast_dynamic_str_[thread_](set|append)_va
+ *
+ * The arguments to this function are the same as those described for
+ * ast_dynamic_str_thread_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_dyn_str_helper(struct ast_dynamic_str **buf, size_t max_len,
+	struct ast_threadstorage *ts, int append, const char *fmt, va_list ap);
+
+/*!
+ * \brief Set a thread locally stored dynamic string using variable arguments
+ *
+ * \arg buf This is the address of a pointer to an ast_dynamic_str which should
+ *      have been retrieved using ast_dynamic_str_thread_get.  It will need to
+ *      be updated in the case that the buffer has to be reallocated to
+ *      accomodate a longer string than what it currently has space for.
+ * \arg max_len This is the maximum length to allow the string buffer to grow
+ *      to.  If this is set to 0, then there is no maximum length.
+ * \arg ts This is a pointer to the thread storage structure declared by using
+ *      the AST_THREADSTORAGE macro.  If declared with 
+ *      AST_THREADSTORAGE(my_buf, my_buf_init), then this argument would be 
+ *      (&my_buf).
+ * \arg fmt This is the format string (printf style)
+ *
+ * \return The return value of this function is the same as that of the printf
+ *         family of functions.
+ *
+ * Example usage:
+ * \code
+ * AST_THREADSTORAGE(my_str, my_str_init);
+ * #define MY_STR_INIT_SIZE   128
+ * ...
+ * void my_func(int arg1, int arg2)
+ * {
+ *      struct ast_dynamic_str *buf;
+ *      va_list ap;
+ *
+ *      if (!(buf = ast_dynamic_str_thread_get(&my_str, MY_STR_INIT_SIZE)))
+ *           return;
+ *      ...
+ *      ast_dynamic_str_thread_set(&buf, 0, &my_str, "arg1: %d  arg2: %d\n",
+ *           arg1, arg2);
+ * 
+ *      printf("This is the string we just built: %s\n", buf->str);
+ *      ...
+ * }
+ * \endcode
+ */
+AST_INLINE_API(
+int __attribute__ ((format (printf, 4, 5))) ast_dynamic_str_thread_set(
+	struct ast_dynamic_str **buf, size_t max_len, 
+	struct ast_threadstorage *ts, const char *fmt, ...),
+{
+	int res;
+	va_list ap;
+
+	va_start(ap, fmt);
+	res = ast_dynamic_str_thread_set_va(buf, max_len, ts, fmt, ap);
+	va_end(ap);
+
+	return res;
+}
+)
+
+/*!
+ * \brief Append to a thread local dynamic string
+ *
+ * The arguments, return values, and usage of this function are the same as
+ * ast_dynamic_str_thread_set().  However, instead of setting a new value for
+ * the string, this function appends to the current value.
+ */
+AST_INLINE_API(
+int __attribute__ ((format (printf, 4, 5))) ast_dynamic_str_thread_append(
+	struct ast_dynamic_str **buf, size_t max_len, 
+	struct ast_threadstorage *ts, const char *fmt, ...),
+{
+	int res;
+	va_list ap;
+
+	va_start(ap, fmt);
+	res = ast_dynamic_str_thread_append_va(buf, max_len, ts, fmt, ap);
+	va_end(ap);
+
+	return res;
+}
+)
+
+/*!
+ * \brief Set a dynamic string
+ *
+ * \arg buf This is the address of a pointer to an ast_dynamic_str.  It will
+ *      need to be updated in the case that the buffer has to be reallocated to
+ *      accommodate a longer string than what it currently has space for.
+ * \arg max_len This is the maximum length to allow the string buffer to grow
+ *      to.  If this is set to 0, then there is no maximum length.
+ *
+ * \return The return value of this function is the same as that of the printf
+ *         family of functions.
+ */
+AST_INLINE_API(
+int __attribute__ ((format (printf, 3, 4))) ast_dynamic_str_set(
+	struct ast_dynamic_str **buf, size_t max_len,
+	const char *fmt, ...),
+{
+	int res;
+	va_list ap;
+	
+	va_start(ap, fmt);
+	res = ast_dynamic_str_thread_set_va(buf, max_len, NULL, fmt, ap);
+	va_end(ap);
+
+	return res;
+}
+)
+
+/*!
+ * \brief Append to a dynamic string
+ *
+ * The arguments, return values, and usage of this function are the same as
+ * ast_dynamic_str_set().  However, this function appends to the string instead
+ * of setting a new value.
+ */
+AST_INLINE_API(
+int __attribute__ ((format (printf, 3, 4))) ast_dynamic_str_append(
+	struct ast_dynamic_str **buf, size_t max_len,
+	const char *fmt, ...),
+{
+	int res;
+	va_list ap;
+	
+	va_start(ap, fmt);
+	res = ast_dynamic_str_thread_append_va(buf, max_len, NULL, fmt, ap);
+	va_end(ap);
+
+	return res;
+}
+)
+
 #endif /* _ASTERISK_STRINGS_H */

Modified: trunk/include/asterisk/threadstorage.h
URL: http://svn.digium.com/view/asterisk/trunk/include/asterisk/threadstorage.h?view=diff&rev=48509&r1=48508&r2=48509
==============================================================================
--- trunk/include/asterisk/threadstorage.h (original)
+++ trunk/include/asterisk/threadstorage.h Fri Dec 15 16:08:46 2006
@@ -56,14 +56,10 @@
  * \brief data for a thread locally stored variable
  */
 struct ast_threadstorage {
-	/*! Ensure that the key is only initialized by one thread */
-	pthread_once_t once;
-	/*! The key used to retrieve this thread's data */
-	pthread_key_t key;
-	/*! The function that initializes the key */
-	void (*key_init)(void);
-	/*! Custom initialization function specific to the object */
-	int (*custom_init)(void *);
+	pthread_once_t once;	/*!< Ensure that the key is only initialized by one thread */
+	pthread_key_t key;	/*!< The key used to retrieve this thread's data */
+	void (*key_init)(void);	/*!< The function that initializes the key */
+	int (*custom_init)(void *); /*!< Custom initialization function specific to the object */
 };
 
 /*!
@@ -161,327 +157,4 @@
 
 void __ast_threadstorage_cleanup(void *);
 
-/*!
- * A dynamic length string. This is just a C string prefixed by a length
- * field. len reflects the actual space allocated, while the string is
- * NUL-terminated as a regular C string.
- * One should never declare a variable with this type, but only a pointer
- * to it, and use ast_dynamic_str_create() to initialize it.
- */
-struct ast_dynamic_str {
-	size_t len;	/*!< The current maximum length of the string */
-	char str[0];	/*!< The string buffer */
-};
-
-/*!
- * \brief Create a dynamic length string
- *
- * \arg init_len This is the initial length of the string buffer
- *
- * \return This function returns a pointer to the dynamic string length.  The
- *         result will be NULL in the case of a memory allocation error.
- *
- * \note The result of this function is dynamically allocated memory, and must
- *       be free()'d after it is no longer needed.
- */
-AST_INLINE_API(
-struct ast_dynamic_str * attribute_malloc ast_dynamic_str_create(size_t init_len),
-{
-	struct ast_dynamic_str *buf;
-
-	if (!(buf = ast_calloc(1, sizeof(*buf) + init_len)))
-		return NULL;
-	
-	buf->len = init_len;
-
-	return buf;
-}
-)
-
-/*!
- * \brief Retrieve a thread locally stored dynamic string
- *
- * \arg ts This is a pointer to the thread storage structure declared by using
- *      the AST_THREADSTORAGE macro.  If declared with 
- *      AST_THREADSTORAGE(my_buf, my_buf_init), then this argument would be 
- *      (&my_buf).
- * \arg init_len This is the initial length of the thread's dynamic string. The
- *      current length may be bigger if previous operations in this thread have
- *      caused it to increase.
- *
- * \return This function will return the thread locally stored dynamic string
- *         associated with the thread storage management variable passed as the
- *         first argument.
- *         The result will be NULL in the case of a memory allocation error.
- *
- * Example usage:
- * \code
- * AST_THREADSTORAGE(my_str, my_str_init);
- * #define MY_STR_INIT_SIZE   128
- * ...
- * void my_func(const char *fmt, ...)
- * {
- *      struct ast_dynamic_str *buf;
- *
- *      if (!(buf = ast_dynamic_str_thread_get(&my_str, MY_STR_INIT_SIZE)))
- *           return;
- *      ...
- * }
- * \endcode
- */
-AST_INLINE_API(
-struct ast_dynamic_str *ast_dynamic_str_thread_get(struct ast_threadstorage *ts,
-	size_t init_len),
-{
-	struct ast_dynamic_str *buf;
-
-	if (!(buf = ast_threadstorage_get(ts, sizeof(*buf) + init_len)))
-		return NULL;
-	
-	if (!buf->len)
-		buf->len = init_len;
-
-	return buf;
-}
-)
-
-/*!
- * \brief Error codes from ast_dynamic_str_thread_build_va()
- */
-enum {
-	/*! An error has occured and the contents of the dynamic string
-	 *  are undefined */
-	AST_DYNSTR_BUILD_FAILED = -1,
-	/*! The buffer size for the dynamic string had to be increased, and
-	 *  ast_dynamic_str_thread_build_va() needs to be called again after
-	 *  a va_end() and va_start().
-	 */
-	AST_DYNSTR_BUILD_RETRY = -2
-};
-
-/*!
- * \brief Set a thread locally stored dynamic string from a va_list
- *
- * \arg buf This is the address of a pointer to an ast_dynamic_str which should
- *      have been retrieved using ast_dynamic_str_thread_get.  It will need to
- *      be updated in the case that the buffer has to be reallocated to
- *      accommodate a longer string than what it currently has space for.
- * \arg max_len This is the maximum length to allow the string buffer to grow
- *      to.  If this is set to 0, then there is no maximum length.
- * \arg ts This is a pointer to the thread storage structure declared by using
- *      the AST_THREADSTORAGE macro.  If declared with 
- *      AST_THREADSTORAGE(my_buf, my_buf_init), then this argument would be 
- *      (&my_buf).
- * \arg fmt This is the format string (printf style)
- * \arg ap This is the va_list
- *
- * \return The return value of this function is the same as that of the printf
- *         family of functions.
- *
- * Example usage:
- * \code
- * AST_THREADSTORAGE(my_str, my_str_init);
- * #define MY_STR_INIT_SIZE   128
- * ...
- * void my_func(const char *fmt, ...)
- * {
- *      struct ast_dynamic_str *buf;
- *      va_list ap;
- *
- *      if (!(buf = ast_dynamic_str_thread_get(&my_str, MY_STR_INIT_SIZE)))
- *           return;
- *      ...
- *      va_start(fmt, ap);
- *      ast_dynamic_str_thread_set_va(&buf, 0, &my_str, fmt, ap);
- *      va_end(ap);
- * 
- *      printf("This is the string we just built: %s\n", buf->str);
- *      ...
- * }
- * \endcode
- */
-#define ast_dynamic_str_thread_set_va(buf, max_len, ts, fmt, ap)                 \
-	({                                                                       \
-		int __res;                                                       \
-		while ((__res = ast_dynamic_str_thread_build_va(buf, max_len,    \
-			ts, 0, fmt, ap)) == AST_DYNSTR_BUILD_RETRY) {            \
-			va_end(ap);                                              \
-			va_start(ap, fmt);                                       \
-		}                                                                \
-		(__res);                                                         \
-	})
-
-/*!
- * \brief Append to a thread local dynamic string using a va_list
- *
- * The arguments, return values, and usage of this are the same as those for
- * ast_dynamic_str_thread_set_va().  However, instead of setting a new value
- * for the string, this will append to the current value.
- */
-#define ast_dynamic_str_thread_append_va(buf, max_len, ts, fmt, ap)              \
-	({                                                                       \
-		int __res;                                                       \
-		while ((__res = ast_dynamic_str_thread_build_va(buf, max_len,    \
-			ts, 1, fmt, ap)) == AST_DYNSTR_BUILD_RETRY) {            \
-			va_end(ap);                                              \
-			va_start(ap, fmt);                                       \
-		}                                                                \
-		(__res);                                                         \
-	})
-
-/*!
- * \brief Core functionality of ast_dynamic_str_thread_(set|append)_va
- *
- * The arguments to this function are the same as those described for
- * ast_dynamic_str_thread_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_dynamic_str_thread_build_va(struct ast_dynamic_str **buf, size_t max_len,
-	struct ast_threadstorage *ts, int append, const char *fmt, va_list ap);
-
-/*!
- * \brief Set a thread locally stored dynamic string using variable arguments
- *
- * \arg buf This is the address of a pointer to an ast_dynamic_str which should
- *      have been retrieved using ast_dynamic_str_thread_get.  It will need to
- *      be updated in the case that the buffer has to be reallocated to
- *      accomodate a longer string than what it currently has space for.
- * \arg max_len This is the maximum length to allow the string buffer to grow
- *      to.  If this is set to 0, then there is no maximum length.
- * \arg ts This is a pointer to the thread storage structure declared by using
- *      the AST_THREADSTORAGE macro.  If declared with 
- *      AST_THREADSTORAGE(my_buf, my_buf_init), then this argument would be 
- *      (&my_buf).
- * \arg fmt This is the format string (printf style)
- *
- * \return The return value of this function is the same as that of the printf
- *         family of functions.
- *
- * Example usage:
- * \code
- * AST_THREADSTORAGE(my_str, my_str_init);
- * #define MY_STR_INIT_SIZE   128
- * ...
- * void my_func(int arg1, int arg2)
- * {
- *      struct ast_dynamic_str *buf;
- *      va_list ap;
- *
- *      if (!(buf = ast_dynamic_str_thread_get(&my_str, MY_STR_INIT_SIZE)))
- *           return;
- *      ...
- *      ast_dynamic_str_thread_set(&buf, 0, &my_str, "arg1: %d  arg2: %d\n",
- *           arg1, arg2);
- * 
- *      printf("This is the string we just built: %s\n", buf->str);
- *      ...
- * }
- * \endcode
- */
-AST_INLINE_API(
-int __attribute__ ((format (printf, 4, 5))) ast_dynamic_str_thread_set(
-	struct ast_dynamic_str **buf, size_t max_len, 
-	struct ast_threadstorage *ts, const char *fmt, ...),
-{
-	int res;
-	va_list ap;
-
-	va_start(ap, fmt);
-	res = ast_dynamic_str_thread_set_va(buf, max_len, ts, fmt, ap);
-	va_end(ap);
-
-	return res;
-}
-)
-
-/*!
- * \brief Append to a thread local dynamic string
- *
- * The arguments, return values, and usage of this function are the same as
- * ast_dynamic_str_thread_set().  However, instead of setting a new value for
- * the string, this function appends to the current value.
- */
-AST_INLINE_API(
-int __attribute__ ((format (printf, 4, 5))) ast_dynamic_str_thread_append(
-	struct ast_dynamic_str **buf, size_t max_len, 
-	struct ast_threadstorage *ts, const char *fmt, ...),
-{
-	int res;
-	va_list ap;
-
-	va_start(ap, fmt);
-	res = ast_dynamic_str_thread_append_va(buf, max_len, ts, fmt, ap);
-	va_end(ap);
-
-	return res;
-}
-)
-
-/*!
- * \brief Set a dynamic string
- *
- * \arg buf This is the address of a pointer to an ast_dynamic_str.  It will
- *      need to be updated in the case that the buffer has to be reallocated to
- *      accommodate a longer string than what it currently has space for.
- * \arg max_len This is the maximum length to allow the string buffer to grow
- *      to.  If this is set to 0, then there is no maximum length.
- *
- * \return The return value of this function is the same as that of the printf
- *         family of functions.
- */
-AST_INLINE_API(
-int __attribute__ ((format (printf, 3, 4))) ast_dynamic_str_set(
-	struct ast_dynamic_str **buf, size_t max_len,
-	const char *fmt, ...),
-{
-	int res;
-	va_list ap;
-	
-	va_start(ap, fmt);
-	res = ast_dynamic_str_thread_set_va(buf, max_len, NULL, fmt, ap);
-	va_end(ap);
-
-	return res;
-}
-)
-
-/*!
- * \brief Append to a dynamic string
- *
- * The arguments, return values, and usage of this function are the same as
- * ast_dynamic_str_set().  However, this function appends to the string instead
- * of setting a new value.
- */
-AST_INLINE_API(
-int __attribute__ ((format (printf, 3, 4))) ast_dynamic_str_append(
-	struct ast_dynamic_str **buf, size_t max_len,
-	const char *fmt, ...),
-{
-	int res;
-	va_list ap;
-	
-	va_start(ap, fmt);
-	res = ast_dynamic_str_thread_append_va(buf, max_len, NULL, fmt, ap);
-	va_end(ap);
-
-	return res;
-}
-)
-
 #endif /* ASTERISK_THREADSTORAGE_H */

Modified: trunk/include/asterisk/utils.h
URL: http://svn.digium.com/view/asterisk/trunk/include/asterisk/utils.h?view=diff&rev=48509&r1=48508&r2=48509
==============================================================================
--- trunk/include/asterisk/utils.h (original)
+++ trunk/include/asterisk/utils.h Fri Dec 15 16:08:46 2006
@@ -32,10 +32,10 @@
 #include <arpa/inet.h>	/* we want to override inet_ntoa */
 #include <netdb.h>
 #include <limits.h>
+#include <string.h>
 
 #include "asterisk/lock.h"
 #include "asterisk/time.h"
-#include "asterisk/strings.h"
 #include "asterisk/logger.h"
 #include "asterisk/compiler.h"
 
@@ -540,4 +540,5 @@
  */
 void ast_enable_packet_fragmentation(int sock);
 
+#include "asterisk/strings.h"
 #endif /* _ASTERISK_UTILS_H */

Modified: trunk/main/utils.c
URL: http://svn.digium.com/view/asterisk/trunk/main/utils.c?view=diff&rev=48509&r1=48508&r2=48509
==============================================================================
--- trunk/main/utils.c (original)
+++ trunk/main/utils.c Fri Dec 15 16:08:46 2006
@@ -972,33 +972,47 @@
 		return -1;
 }
 
-int ast_dynamic_str_thread_build_va(struct ast_dynamic_str **buf, size_t max_len,
+/*!
+ * core handler for dynamic strings.
+ * This is not meant to be called directly, but rather through the
+ * various wrapper macros
+ *	ast_dynamic_str_set(...)
+ *	ast_dynamic_str_append(...)
+ *	ast_dynamic_str_thread_set(...)
+ *	ast_dynamic_str_thread_append(...)
+ */
+int __ast_dyn_str_helper(struct ast_dynamic_str **buf, size_t max_len,
 	struct ast_threadstorage *ts, int append, const char *fmt, va_list ap)
 {
 	int res, need;
-	int offset = (append && (*buf)->len) ? strlen((*buf)->str) : 0;
-
+	int offset = (append && (*buf)->len) ? (*buf)->used : 0;
+
+	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;
-	/* Check to see if there was not enough space in the string buffer to prepare
-	 * the string.  Also, if a maximum length is present, make sure the current
-	 * length is less than the maximum before increasing the size. */
+	/*
+	 * 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) ) {
-		/* Set the new size of the string buffer to be the size needed
-		 * to hold the resulting string (res) plus one byte for the
-		 * terminating '\0'.  If this size is greater than the max, set
-		 * the new length to be the maximum allowed. */
-		if (max_len && max_len < need)
+		if (max_len && max_len < need)	/* truncate as needed */
 			need = max_len;
 
+		/* We can only realloc malloc'ed space. */
+		if ((*buf)->type != DS_MALLOC)
+			return AST_DYNSTR_BUILD_FAILED;
 		*buf = ast_realloc(*buf, need + sizeof(struct ast_dynamic_str));
-		if (*buf == NULL)
+		if (*buf == NULL) /* XXX watch out, we leak memory here */
 			return AST_DYNSTR_BUILD_FAILED;
 		(*buf)->len = need;
 
-		/* Truncate the partial write. */
-		(*buf)->str[offset] = '\0';
+		(*buf)->str[offset] = '\0';	/* Truncate the partial write. */
 
 		if (ts)
 			pthread_setspecific(ts->key, *buf);
@@ -1007,6 +1021,8 @@
 		 * vsnprintf() again. */
 		return AST_DYNSTR_BUILD_RETRY;
 	}
+	/* update space used, keep in mind the truncation */
+	(*buf)->used = (res + offset > (*buf)->len) ? (*buf)->len : res + offset;
 
 	return res;
 }



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