svn commit: r343480 - head/lib/libfigpar

[Colin Percival]

On 1/26/19 1:36 PM, Rodney W. Grimes wrote:
>> Author: se
>> Date: Sat Jan 26 21:30:26 2019
>> New Revision: 343480
>> URL: https://svnweb.freebsd.org/changeset/base/343480
>>
>> Log:
>>   Silence Clang Scan warning about potentially unsafe use of strcpy.
>>   
>>   While this is a false positive, the use of strdup() simplifies the code.
> 
> Though that might be true, it also has to recalculate the
> length of the string which was already known by slen.
> 
> I am not sure how often this code is called,
> but that is wasted cycles in a library.

The length of the string was already being recalculated, by strcpy.

It seems to me that this could be written as

	temp = malloc(slen + 1);
	if (temp == NULL) /* could not allocate memory */
		return (-1);
	memcpy(temp, source, slen + 1);

which avoids both recalculating the string length and using strcpy?

>> Modified: head/lib/libfigpar/string_m.c
>> ==============================================================================
>> --- head/lib/libfigpar/string_m.c	Sat Jan 26 20:43:28 2019	(r343479)
>> +++ head/lib/libfigpar/string_m.c	Sat Jan 26 21:30:26 2019	(r343480)
>> @@ -119,10 +119,9 @@ replaceall(char *source, const char *find, const char 
>>  
>>  	/* If replace is longer than find, we'll need to create a temp copy */
>>  	if (rlen > flen) {
>> -		temp = malloc(slen + 1);
>> -		if (errno != 0) /* could not allocate memory */
>> +		temp = strdup(source);
>> +		if (temp == NULL) /* could not allocate memory */
>>  			return (-1);
>> -		strcpy(temp, source);
>>  	} else
>>  		temp = source;

-- 
Colin Percival
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