Some varbuf enhancements:

- Introduce new ap_varbuf_pdup() and ap_varbuf_regsub() functions.
- Fix some bugs in ap_varbuf_strmemcat().
- Make ap_varbuf.buf point to an empty string if no buffer has been allocated,
  yet.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1176018 13f79535-47bb-0310-9956-ffa450edef68

2 files changed, 39 insertions, 2 deletions

diff --git a/include/ap_mmn.h b/include/ap_mmn.h
index 94796ddd68..7a0f04943f 100644
--- a/include/ap_mmn.h
+++ b/include/ap_mmn.h
@@ -354,6 +354,7 @@
  * 20110724.7 (2.3.15-dev) add ap_random_insecure_bytes(), ap_random_pick()
  * 20110724.8 (2.3.15-dev) add ap_abort_on_oom(), ap_malloc(), ap_calloc(),
  *                         ap_realloc()
+ * 20110724.9 (2.3.15-dev) add ap_varbuf_pdup() and ap_varbuf_regsub()
  */
 
 #define MODULE_MAGIC_COOKIE 0x41503234UL /* "AP24" */
@@ -361,7 +362,7 @@
 #ifndef MODULE_MAGIC_NUMBER_MAJOR
 #define MODULE_MAGIC_NUMBER_MAJOR 20110724
 #endif
-#define MODULE_MAGIC_NUMBER_MINOR 8                    /* 0...n */
+#define MODULE_MAGIC_NUMBER_MINOR 9                    /* 0...n */
 
 /**
  * Determine if the server's current MODULE_MAGIC_NUMBER is at least a
diff --git a/include/util_varbuf.h b/include/util_varbuf.h
index ceb46feb3c..dc55e2c90c 100644
--- a/include/util_varbuf.h
+++ b/include/util_varbuf.h
@@ -36,7 +36,7 @@ struct ap_varbuf_info;
 
 /** A resizable buffer */
 struct ap_varbuf {
-    /** the actual buffer */
+    /** the actual buffer; will point to a const '\0' if avail == 0 */
     char *buf;
 
     /** allocated size of the buffer (minus one for the final \0);
@@ -100,6 +100,26 @@ AP_DECLARE(void) ap_varbuf_free(struct ap_varbuf *vb);
 AP_DECLARE(void) ap_varbuf_strmemcat(struct ap_varbuf *vb, const char *str,
                                      int len);
 
+/** Duplicate an ap_varbuf's content into pool memory
+ * @param p the pool to allocate from
+ * @param vb the ap_varbuf to copy from
+ * @param prepend an optional buffer to prepend (may be NULL)
+ * @param prepend_len length of prepend
+ * @param append an optional buffer to append (may be NULL)
+ * @param append_len length of append
+ * @param new_len where to store the length of the resulting string
+ *        (may be NULL)
+ * @return the new string
+ * @note ap_varbuf_pdup() uses vb->strlen to determine how much memory to
+ *       copy. It works even if 0-bytes are embedded in vb->buf, prepend, or
+ *       append
+ */
+AP_DECLARE(char *) ap_varbuf_pdup(apr_pool_t *p, struct ap_varbuf *vb,
+                                  const char *prepend, apr_size_t prepend_len,
+                                  const char *append, apr_size_t append_len,
+                                  apr_size_t *new_len);
+
+
 /** Concatenate a string to an ap_varbuf
  * @param vb pointer to the ap_varbuf struct
  * @param str the string to append
@@ -107,6 +127,22 @@ AP_DECLARE(void) ap_varbuf_strmemcat(struct ap_varbuf *vb, const char *str,
  */
 #define ap_varbuf_strcat(vb, str) ap_varbuf_strmemcat(vb, str, strlen(str))
 
+/** Perform string substitutions based on regexp match, using an ap_varbuf.
+ * This function behaves like ap_pregsub(), but appends to an ap_varbuf
+ * instead of allocating the result from a pool.
+ * @param input An arbitrary string containing $1 through $9.  These are
+ *              replaced with the corresponding matched sub-expressions
+ * @param source The string that was originally matched to the regex
+ * @param nmatch the nmatch returned from ap_pregex
+ * @param pmatch the pmatch array returned from ap_pregex
+ * @note Just like ap_pregsub(), this function does not copy the part of
+ *       *source before the matching part (i.e. the first pmatch[0].rm_so
+ *       characters).
+ */
+AP_DECLARE(void) ap_varbuf_regsub(struct ap_varbuf *vb, const char *input,
+                                  const char *source, size_t nmatch,
+                                  ap_regmatch_t pmatch[]);
+
 /** Read a line from an ap_configfile_t into an ap_varbuf.
  * @param vb pointer to the ap_varbuf struct
  * @param cfg pointer to the ap_configfile_t