Am 30.11.2012 11:32, schrieb Gerald Dachs:
Am 2012-11-30 10:17, schrieb Lars Hanisch:
Looks like the pointer returned by sscanf is not valid:
32: bool tComponent::FromString(const char *s) 33: { 34: unsigned int Stream, Type; 35: int n = sscanf(s, "%X %02X %7s %a[^\n]", &Stream, &Type, language, &description); // 7 = MAXLANGCODE2 - 1 36: if (n != 4 || isempty(description)) { 37: free(description); 38: description = NULL; 39: } 40: stream = Stream; 41: type = Type; 42: return n >= 3; 43: }
From man sscanf:
The GNU C library supports a nonstandard extension that causes the library to dynamically allocate a string of sufficient size for input strings for the %s and %a[range] conversion specifiers.
This is the reason why it doesn't work with ulibc.
Then there should be a malloc or something similiar for description:
32: bool tComponent::FromString(const char *s) 33: { 34: unsigned int Stream, Type; description = malloc(strlen(s)); description[0] = 0; 35: int n = sscanf(s, "%X %02X %7s %a[^\n]", &Stream, &Type, language, &description); // 7 = MAXLANGCODE2 - 1 36: if (n != 4 || isempty(description)) { 37: free(description); 38: description = NULL; 39: } 40: stream = Stream; 41: type = Type; 42: return n >= 3; 43: }
A check for description != NULL before the free call is not needed.
But this is not the only place in the vdr code, where %a is used...
Lars.
Gerald
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