65 lines
1.1 KiB
C
65 lines
1.1 KiB
C
/*
|
|
* compare
|
|
*
|
|
* Compares two files and prints out some
|
|
* statistics on how they differ.
|
|
*
|
|
* This is *NOT* diff.
|
|
*/
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
|
|
#define CHUNK_SIZE 1024
|
|
|
|
int main(int argc, char * argv[]) {
|
|
if (argc < 3) {
|
|
fprintf(stderr, "Need two files to compare.\n");
|
|
return 1;
|
|
}
|
|
|
|
FILE * a = fopen(argv[1], "r");
|
|
FILE * b = fopen(argv[2], "r");
|
|
size_t lengtha, lengthb;
|
|
|
|
fseek(a, 0, SEEK_END);
|
|
lengtha = ftell(a);
|
|
fseek(a, 0, SEEK_SET);
|
|
|
|
fseek(b, 0, SEEK_END);
|
|
lengthb = ftell(b);
|
|
fseek(b, 0, SEEK_SET);
|
|
|
|
fprintf(stderr,"[%d bytes and %d bytes]\n", lengtha, lengthb);
|
|
|
|
char bufa[CHUNK_SIZE];
|
|
char bufb[CHUNK_SIZE];
|
|
|
|
int chunk = 0;
|
|
size_t read = 0;
|
|
|
|
while (read < lengtha) {
|
|
memset(bufa, 0x0, CHUNK_SIZE);
|
|
memset(bufb, 0x0, CHUNK_SIZE);
|
|
fread(bufa, 1, CHUNK_SIZE, a);
|
|
fread(bufb, 1, CHUNK_SIZE, b);
|
|
size_t different = 0;
|
|
for (int i = 0; i < CHUNK_SIZE; ++i) {
|
|
if (bufa[i] != bufb[i])
|
|
different++;
|
|
}
|
|
|
|
if (different > 0) {
|
|
printf("Chunk %d has %d differing bytes.\n", chunk, different);
|
|
}
|
|
|
|
read += CHUNK_SIZE;
|
|
chunk++;
|
|
}
|
|
|
|
fclose(a);
|
|
fclose(b);
|
|
|
|
|
|
return 0;
|
|
}
|