git/diffcore-pickaxe.c
Junio C Hamano 2002eed6c9 [PATCH] diffcore-pickaxe: switch to "counting" behaviour.
Instead of finding old/new pair that one side has and the
other side does not have the specified string, find old/new pair
that contains the specified string as a substring different
number of times.  This would still not catch a case where you
introduce two static variable declarations and remove two static
function definitions from a file with -S"static", but would make
it behave a bit more intuitively.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-23 20:27:49 -07:00

105 lines
2.5 KiB
C

/*
* Copyright (C) 2005 Junio C Hamano
*/
#include "cache.h"
#include "diff.h"
#include "diffcore.h"
static unsigned int contains(struct diff_filespec *one,
const char *needle, unsigned long len)
{
unsigned int cnt;
unsigned long offset, sz;
const char *data;
if (diff_populate_filespec(one, 0))
return 0;
sz = one->size;
data = one->data;
cnt = 0;
/* Yes, I've heard of strstr(), but the thing is *data may
* not be NUL terminated. Sue me.
*/
for (offset = 0; offset + len <= sz; offset++) {
/* we count non-overlapping occurrences of needle */
if (!memcmp(needle, data + offset, len)) {
offset += len - 1;
cnt++;
}
}
return cnt;
}
void diffcore_pickaxe(const char *needle, int opts)
{
struct diff_queue_struct *q = &diff_queued_diff;
unsigned long len = strlen(needle);
int i, has_changes;
struct diff_queue_struct outq;
outq.queue = NULL;
outq.nr = outq.alloc = 0;
if (opts & DIFF_PICKAXE_ALL) {
/* Showing the whole changeset if needle exists */
for (i = has_changes = 0; !has_changes && i < q->nr; i++) {
struct diff_filepair *p = q->queue[i];
if (!DIFF_FILE_VALID(p->one)) {
if (!DIFF_FILE_VALID(p->two))
continue; /* ignore unmerged */
/* created */
if (contains(p->two, needle, len))
has_changes++;
}
else if (!DIFF_FILE_VALID(p->two)) {
if (contains(p->one, needle, len))
has_changes++;
}
else if (!diff_unmodified_pair(p) &&
contains(p->one, needle, len) !=
contains(p->two, needle, len))
has_changes++;
}
if (has_changes)
return; /* not munge the queue */
/* otherwise we will clear the whole queue
* by copying the empty outq at the end of this
* function, but first clear the current entries
* in the queue.
*/
for (i = 0; i < q->nr; i++)
diff_free_filepair(q->queue[i]);
}
else
/* Showing only the filepairs that has the needle */
for (i = 0; i < q->nr; i++) {
struct diff_filepair *p = q->queue[i];
has_changes = 0;
if (!DIFF_FILE_VALID(p->one)) {
if (!DIFF_FILE_VALID(p->two))
; /* ignore unmerged */
/* created */
else if (contains(p->two, needle, len))
has_changes = 1;
}
else if (!DIFF_FILE_VALID(p->two)) {
if (contains(p->one, needle, len))
has_changes = 1;
}
else if (!diff_unmodified_pair(p) &&
contains(p->one, needle, len) !=
contains(p->two, needle, len))
has_changes = 1;
if (has_changes)
diff_q(&outq, p);
else
diff_free_filepair(p);
}
free(q->queue);
*q = outq;
return;
}