From 1313c1284700f2cb9882b4390989e10a4b51df00 Mon Sep 17 00:00:00 2001
From: Richard Mudgett <rmudgett@digium.com>
Date: Tue, 20 Sep 2011 22:54:21 +0000
Subject: [PATCH] Merged revisions 337119 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/10
........
r337119 | rmudgett | 2011-09-20 17:47:45 -0500 (Tue, 20 Sep 2011) | 16 lines
Fix crash with STRREPLACE function.
The ast_func_read() function calls the .read2 callback with the len
parameter set to zero indicating no size restrictions on the supplied
ast_str buffer. The value was used to dimension a local starts[] array
with the array subsequently used.
* Reworked the strreplace() function to perform the string replacement in
a straight forward manner. Eliminated the need for the starts[] array.
(closes issue ASTERISK-18545)
Reported by: Federico Alves
Patches:
jira_asterisk_18545_v10.patch (license #5621) patch uploaded by rmudgett
Tested by: rmudgett, Federico Alves
........
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@337123 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---
funcs/func_strings.c | 87 +++++++++++++++++++++-----------------------
1 file changed, 42 insertions(+), 45 deletions(-)
diff --git a/funcs/func_strings.c b/funcs/func_strings.c
index d9d0320314..5d7569bfef 100644
--- a/funcs/func_strings.c
+++ b/funcs/func_strings.c
@@ -859,14 +859,12 @@ static struct ast_custom_function replace_function = {
static int strreplace(struct ast_channel *chan, const char *cmd, char *data, struct ast_str **buf, ssize_t len)
{
- char *starts[len]; /* marks starts of substrings */
char *varsubstr; /* substring for input var */
- int count_len = 0; /* counter for starts */
- char *p; /* tracks position of cursor for search and replace */
+ char *start; /* Starting pos of substring search. */
+ char *end; /* Ending pos of substring search. */
int find_size; /* length of given find-string */
- int max_matches; /* number of matches we find before terminating search */
-
- int x; /* loop counter */
+ unsigned max_matches; /* number of matches we find before terminating search */
+ unsigned count; /* loop counter */
struct ast_str *str = ast_str_thread_get(&result_buf, 16); /* Holds the data obtained from varname */
AST_DECLARE_APP_ARGS(args,
@@ -874,16 +872,25 @@ static int strreplace(struct ast_channel *chan, const char *cmd, char *data, str
AST_APP_ARG(find_string);
AST_APP_ARG(replace_string);
AST_APP_ARG(max_replacements);
+ AST_APP_ARG(other); /* Any remining unused arguments */
);
- AST_STANDARD_APP_ARGS(args, data);
+ /* Guarantee output string is empty to start with. */
+ ast_str_reset(*buf);
- if (!str) { /* If we failed to allocate str, forget it. We failed. */
+ if (!str) {
+ /* We failed to allocate str, forget it. We failed. */
return -1;
}
- if (args.argc < 2) { /* Didn't receive enough arguments to do anything */
- ast_log(LOG_ERROR, "Usage: %s(<varname>,<find-string>[,<replace-string>, <max-replacements>])\n", cmd);
+ /* Parse the arguments. */
+ AST_STANDARD_APP_ARGS(args, data);
+
+ if (args.argc < 2) {
+ /* Didn't receive enough arguments to do anything */
+ ast_log(LOG_ERROR,
+ "Usage: %s(<varname>,<find-string>[,<replace-string>,[<max-replacements>]])\n",
+ cmd);
return -1;
}
@@ -892,54 +899,44 @@ static int strreplace(struct ast_channel *chan, const char *cmd, char *data, str
return -1;
}
- /* set varsubstr to the matching variable */
- varsubstr = alloca(strlen(args.varname) + 4);
- sprintf(varsubstr, "${%s}", args.varname);
- ast_str_substitute_variables(&str, 0, chan, varsubstr);
-
- p = ast_str_buffer(str);
-
/* Zero length find strings are a no-no. Kill the function if we run into one. */
if (ast_strlen_zero(args.find_string)) {
- ast_log(LOG_ERROR, "The <find-string> must have length > 0\n");
+ ast_log(LOG_ERROR, "No <find-string> specified\n");
return -1;
}
find_size = strlen(args.find_string);
- /* If the replace string is a null pointer, set it to an empty string */
- if (!args.replace_string) {
- args.replace_string = "";
- }
+ /* set varsubstr to the matching variable */
+ varsubstr = alloca(strlen(args.varname) + 4);
+ sprintf(varsubstr, "${%s}", args.varname);
+ ast_str_substitute_variables(&str, 0, chan, varsubstr);
- /*
- * If max_replacements specified and is a number, max_matches will become that.
- * otherwise, just go the length of the input string
- */
- if (!(args.max_replacements && (max_matches = atoi(args.max_replacements)))) {
- max_matches = strlen(p);
+ /* Determine how many replacements are allowed. */
+ if (!args.max_replacements
+ || (max_matches = atoi(args.max_replacements)) <= 0) {
+ /* Unlimited replacements are allowed. */
+ max_matches = -1;
}
- /* Iterate through string finding matches until it is exhausted or we reach max_matches */
- for (x = 0; x < max_matches; x++) {
- if ((p = strstr(p, args.find_string))) {
- starts[count_len++] = p;
- *p = '\0';
- p += find_size;
- } else {
+ /* Generate the search and replaced string. */
+ start = ast_str_buffer(str);
+ for (count = 0; count < max_matches; ++count) {
+ end = strstr(start, args.find_string);
+ if (!end) {
+ /* Did not find a matching substring in the remainder. */
break;
}
- }
- p = ast_str_buffer(str);
-
- /* here we rebuild the string with the replaced words by using fancy ast_string_append on the buffer */
- for (x = 0; x < count_len; x++) {
- ast_str_append(buf, len, "%s", p);
- p = starts[x];
- p += find_size;
- ast_str_append(buf, len, "%s", args.replace_string);
+ /* Replace the found substring. */
+ *end = '\0';
+ ast_str_append(buf, len, "%s", start);
+ if (args.replace_string) {
+ /* Append the replacement string */
+ ast_str_append(buf, len, "%s", args.replace_string);
+ }
+ start = end + find_size;
}
- ast_str_append(buf, len, "%s", p);
+ ast_str_append(buf, len, "%s", start);
return 0;
}
--
GitLab