zlib gzread function error when read .gz file? - c++

Question

like title, here is my code:
int decompress_one_file(char *infilename, char *outfilename)
{
gzFile infile = gzopen(infilename, "rb");
FILE *outfile = fopen(outfilename, "wb");
if (!infile || !outfile) return -1;
char buffer[128] = {NULL};
int num_read = 0;
num_read = gzread(infile, buffer, sizeof(buffer)); // crash here
while (num_read > 0) {
fwrite(buffer, 1, num_read, outfile);
}
gzclose(infile);
fclose(outfile);
return 0;
}
when my console-app run to gzread(), its crash, I don't know what type of error is this?. zlib version: 1.2.11
update compress function:
int compress_one_file(char *infilename, char *outfilename)
{
FILE *infile = fopen(infilename, "rb");
gzFile outfile = gzopen(outfilename, "wb");
if (!infile || !outfile) return -1;
char inbuffer[128] = {NULL};
int num_read = 0;
unsigned long total_read = 0, total_wrote = 0;
while ((num_read = fread(inbuffer, 1, sizeof(inbuffer), infile)) > 0) {
total_read += num_read;
gzwrite(outfile, inbuffer, num_read);
}
fclose(infile);
gzclose(outfile);
return 0;
}
Error that shows up:
Anyone got an idea about this error?

Answer 1

I checked and it works fine at my workstation. May be here is a issue with gzipped file?
Could you show a file that give a crash?
But in any case you have a infinity loop of fwrite:
int num_read = 0;
while ((num_read = gzread(infile, buffer, sizeof(buffer))) > 0) {
while (num_read > 0) {
num_read -= fwrite(buffer, 1, num_read, outfile);
}
}