Pull in a piece of murf's 88166 patch that makes it safe to call

pbx_substitute_variables_helper_full with a non-zero'd buffer

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@194322 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/main/pbx.c b/main/pbx.c
index 2129ef55c3e5d34b8ec63de6b398acb0d0d45060..8fa993501db44d7e29636aef04ddc8debab0dfd6 100644 (file)
--- a/main/pbx.c
+++ b/main/pbx.c
@@ -1573,8 +1573,7 @@ int ast_func_write(struct ast_channel *chan, char *function, const char *value)
 
 static void pbx_substitute_variables_helper_full(struct ast_channel *c, struct varshead *headp, const char *cp1, char *cp2, int count)
 {
-       /* Substitutes variables into cp2, based on string cp1, and assuming cp2 to be
-          zero-filled */
+       /* Substitutes variables into cp2, based on string cp1, cp2 NO LONGER NEEDS TO BE ZEROED OUT!!!!  */
        char *cp4;
        const char *tmp, *whereweare;
        int length, offset, offset2, isfunction;
@@ -1584,6 +1583,7 @@ static void pbx_substitute_variables_helper_full(struct ast_channel *c, struct v
        char *vars, *vare;
        int pos, brackets, needsub, len;
 
+       *cp2 = 0; /* just in case nothing ends up there */
        whereweare=tmp=cp1;
        while (!ast_strlen_zero(whereweare) && count) {
                /* Assume we're copying the whole remaining string */
@@ -1617,6 +1617,7 @@ static void pbx_substitute_variables_helper_full(struct ast_channel *c, struct v
                        count -= pos;
                        cp2 += pos;
                        whereweare += pos;
+                       *cp2 = 0;
                }
 
                if (nextvar) {
@@ -1640,7 +1641,7 @@ static void pbx_substitute_variables_helper_full(struct ast_channel *c, struct v
                                vare++;
                        }
                        if (brackets)
-                               ast_log(LOG_NOTICE, "Error in extension logic (missing '}')\n");
+                               ast_log(LOG_WARNING, "Error in extension logic (missing '}')\n");
                        len = vare - vars - 1;
 
                        /* Skip totally over variable string */
@@ -1657,7 +1658,6 @@ static void pbx_substitute_variables_helper_full(struct ast_channel *c, struct v
                                if (!ltmp)
                                        ltmp = alloca(VAR_BUF_SIZE);
 
-                               memset(ltmp, 0, VAR_BUF_SIZE);
                                pbx_substitute_variables_helper_full(c, headp, var, ltmp, VAR_BUF_SIZE - 1);
                                vars = ltmp;
                        } else {
@@ -1703,6 +1703,7 @@ static void pbx_substitute_variables_helper_full(struct ast_channel *c, struct v
                                memcpy(cp2, cp4, length);
                                count -= length;
                                cp2 += length;
+                               *cp2 = 0;
                        }
                } else if (nextexp) {
                        /* We have an expression.  Find the start and end, and determine
@@ -1713,7 +1714,7 @@ static void pbx_substitute_variables_helper_full(struct ast_channel *c, struct v
                        needsub = 0;
 
                        /* Find the end of it */
-                       while(brackets && *vare) {
+                       while (brackets && *vare) {
                                if ((vare[0] == '$') && (vare[1] == '[')) {
                                        needsub++;
                                        brackets++;
@@ -1729,7 +1730,7 @@ static void pbx_substitute_variables_helper_full(struct ast_channel *c, struct v
                                vare++;
                        }
                        if (brackets)
-                               ast_log(LOG_NOTICE, "Error in extension logic (missing ']')\n");
+                               ast_log(LOG_WARNING, "Error in extension logic (missing ']')\n");
                        len = vare - vars - 1;
 
                        /* Skip totally over expression */
@@ -1746,7 +1747,6 @@ static void pbx_substitute_variables_helper_full(struct ast_channel *c, struct v
                                if (!ltmp)
                                        ltmp = alloca(VAR_BUF_SIZE);
 
-                               memset(ltmp, 0, VAR_BUF_SIZE);
                                pbx_substitute_variables_helper_full(c, headp, var, ltmp, VAR_BUF_SIZE - 1);
                                vars = ltmp;
                        } else {
@@ -1760,6 +1760,7 @@ static void pbx_substitute_variables_helper_full(struct ast_channel *c, struct v
                                        ast_log(LOG_DEBUG, "Expression result is '%s'\n", cp2);
                                count -= length;
                                cp2 += length;
+                               *cp2 = 0;
                        }
                }
        }