strings.h: Ensure ast_str_buffer(…) returns a 0 terminated string.

If a dynamic string is created with an initial length of 0,
`ast_str_buffer(…)` will return an invalid pointer.

This was a secondary discovery when fixing #65.
This commit is contained in:
Sean Bright 2024-02-17 14:41:38 -05:00 committed by asterisk-org-access-app[bot]
parent 650240aa92
commit a829125e37
1 changed files with 4 additions and 1 deletions

View File

@ -753,7 +753,10 @@ char * attribute_pure ast_str_buffer(const struct ast_str *buf),
* being returned; eventually, it should become truly const
* and only be modified via accessor functions
*/
return (char *) buf->__AST_STR_STR;
if (__builtin_expect(buf->__AST_STR_LEN > 0, 1)) {
return (char *) buf->__AST_STR_STR;
}
return "";
}
)