mirror of
https://github.com/git/git
synced 2024-08-27 11:39:22 +00:00
![Jeff King](/assets/img/avatar_default.png)
The xdiff library always emits hunk header lines to our callbacks as formatted strings like "@@ -a,b +c,d @@\n". This is convenient if we're going to output a diff, but less so if we actually need to compute using those numbers, which requires re-parsing the line. In preparation for moving away from this, let's teach xdiff a new callback function which gets the broken-out hunk information. To help callers that don't want to use this new callback, if it's NULL we'll continue to format the hunk header into a string. Note that this function renames the "outf" callback to "out_line", as well. This isn't strictly necessary, but helps in two ways: 1. Now that there are two callbacks, it's nice to use more descriptive names. 2. Many callers did not zero the emit_callback_data struct, and needed to be modified to set ecb.out_hunk to NULL. By changing the name of the existing struct member, that guarantees that any new callers from in-flight topics will break the build and be examined manually. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
439 lines
9.7 KiB
C
439 lines
9.7 KiB
C
/*
|
|
* LibXDiff by Davide Libenzi ( File Differential Library )
|
|
* Copyright (C) 2003 Davide Libenzi
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, see
|
|
* <http://www.gnu.org/licenses/>.
|
|
*
|
|
* Davide Libenzi <davidel@xmailserver.org>
|
|
*
|
|
*/
|
|
|
|
#include <limits.h>
|
|
#include <assert.h>
|
|
#include "xinclude.h"
|
|
|
|
|
|
|
|
|
|
long xdl_bogosqrt(long n) {
|
|
long i;
|
|
|
|
/*
|
|
* Classical integer square root approximation using shifts.
|
|
*/
|
|
for (i = 1; n > 0; n >>= 2)
|
|
i <<= 1;
|
|
|
|
return i;
|
|
}
|
|
|
|
|
|
int xdl_emit_diffrec(char const *rec, long size, char const *pre, long psize,
|
|
xdemitcb_t *ecb) {
|
|
int i = 2;
|
|
mmbuffer_t mb[3];
|
|
|
|
mb[0].ptr = (char *) pre;
|
|
mb[0].size = psize;
|
|
mb[1].ptr = (char *) rec;
|
|
mb[1].size = size;
|
|
if (size > 0 && rec[size - 1] != '\n') {
|
|
mb[2].ptr = (char *) "\n\\ No newline at end of file\n";
|
|
mb[2].size = strlen(mb[2].ptr);
|
|
i++;
|
|
}
|
|
if (ecb->out_line(ecb->priv, mb, i) < 0) {
|
|
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void *xdl_mmfile_first(mmfile_t *mmf, long *size)
|
|
{
|
|
*size = mmf->size;
|
|
return mmf->ptr;
|
|
}
|
|
|
|
|
|
long xdl_mmfile_size(mmfile_t *mmf)
|
|
{
|
|
return mmf->size;
|
|
}
|
|
|
|
|
|
int xdl_cha_init(chastore_t *cha, long isize, long icount) {
|
|
|
|
cha->head = cha->tail = NULL;
|
|
cha->isize = isize;
|
|
cha->nsize = icount * isize;
|
|
cha->ancur = cha->sncur = NULL;
|
|
cha->scurr = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
void xdl_cha_free(chastore_t *cha) {
|
|
chanode_t *cur, *tmp;
|
|
|
|
for (cur = cha->head; (tmp = cur) != NULL;) {
|
|
cur = cur->next;
|
|
xdl_free(tmp);
|
|
}
|
|
}
|
|
|
|
|
|
void *xdl_cha_alloc(chastore_t *cha) {
|
|
chanode_t *ancur;
|
|
void *data;
|
|
|
|
if (!(ancur = cha->ancur) || ancur->icurr == cha->nsize) {
|
|
if (!(ancur = (chanode_t *) xdl_malloc(sizeof(chanode_t) + cha->nsize))) {
|
|
|
|
return NULL;
|
|
}
|
|
ancur->icurr = 0;
|
|
ancur->next = NULL;
|
|
if (cha->tail)
|
|
cha->tail->next = ancur;
|
|
if (!cha->head)
|
|
cha->head = ancur;
|
|
cha->tail = ancur;
|
|
cha->ancur = ancur;
|
|
}
|
|
|
|
data = (char *) ancur + sizeof(chanode_t) + ancur->icurr;
|
|
ancur->icurr += cha->isize;
|
|
|
|
return data;
|
|
}
|
|
|
|
long xdl_guess_lines(mmfile_t *mf, long sample) {
|
|
long nl = 0, size, tsize = 0;
|
|
char const *data, *cur, *top;
|
|
|
|
if ((cur = data = xdl_mmfile_first(mf, &size)) != NULL) {
|
|
for (top = data + size; nl < sample && cur < top; ) {
|
|
nl++;
|
|
if (!(cur = memchr(cur, '\n', top - cur)))
|
|
cur = top;
|
|
else
|
|
cur++;
|
|
}
|
|
tsize += (long) (cur - data);
|
|
}
|
|
|
|
if (nl && tsize)
|
|
nl = xdl_mmfile_size(mf) / (tsize / nl);
|
|
|
|
return nl + 1;
|
|
}
|
|
|
|
int xdl_blankline(const char *line, long size, long flags)
|
|
{
|
|
long i;
|
|
|
|
if (!(flags & XDF_WHITESPACE_FLAGS))
|
|
return (size <= 1);
|
|
|
|
for (i = 0; i < size && XDL_ISSPACE(line[i]); i++)
|
|
;
|
|
|
|
return (i == size);
|
|
}
|
|
|
|
/*
|
|
* Have we eaten everything on the line, except for an optional
|
|
* CR at the very end?
|
|
*/
|
|
static int ends_with_optional_cr(const char *l, long s, long i)
|
|
{
|
|
int complete = s && l[s-1] == '\n';
|
|
|
|
if (complete)
|
|
s--;
|
|
if (s == i)
|
|
return 1;
|
|
/* do not ignore CR at the end of an incomplete line */
|
|
if (complete && s == i + 1 && l[i] == '\r')
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
int xdl_recmatch(const char *l1, long s1, const char *l2, long s2, long flags)
|
|
{
|
|
int i1, i2;
|
|
|
|
if (s1 == s2 && !memcmp(l1, l2, s1))
|
|
return 1;
|
|
if (!(flags & XDF_WHITESPACE_FLAGS))
|
|
return 0;
|
|
|
|
i1 = 0;
|
|
i2 = 0;
|
|
|
|
/*
|
|
* -w matches everything that matches with -b, and -b in turn
|
|
* matches everything that matches with --ignore-space-at-eol,
|
|
* which in turn matches everything that matches with --ignore-cr-at-eol.
|
|
*
|
|
* Each flavor of ignoring needs different logic to skip whitespaces
|
|
* while we have both sides to compare.
|
|
*/
|
|
if (flags & XDF_IGNORE_WHITESPACE) {
|
|
goto skip_ws;
|
|
while (i1 < s1 && i2 < s2) {
|
|
if (l1[i1++] != l2[i2++])
|
|
return 0;
|
|
skip_ws:
|
|
while (i1 < s1 && XDL_ISSPACE(l1[i1]))
|
|
i1++;
|
|
while (i2 < s2 && XDL_ISSPACE(l2[i2]))
|
|
i2++;
|
|
}
|
|
} else if (flags & XDF_IGNORE_WHITESPACE_CHANGE) {
|
|
while (i1 < s1 && i2 < s2) {
|
|
if (XDL_ISSPACE(l1[i1]) && XDL_ISSPACE(l2[i2])) {
|
|
/* Skip matching spaces and try again */
|
|
while (i1 < s1 && XDL_ISSPACE(l1[i1]))
|
|
i1++;
|
|
while (i2 < s2 && XDL_ISSPACE(l2[i2]))
|
|
i2++;
|
|
continue;
|
|
}
|
|
if (l1[i1++] != l2[i2++])
|
|
return 0;
|
|
}
|
|
} else if (flags & XDF_IGNORE_WHITESPACE_AT_EOL) {
|
|
while (i1 < s1 && i2 < s2 && l1[i1] == l2[i2]) {
|
|
i1++;
|
|
i2++;
|
|
}
|
|
} else if (flags & XDF_IGNORE_CR_AT_EOL) {
|
|
/* Find the first difference and see how the line ends */
|
|
while (i1 < s1 && i2 < s2 && l1[i1] == l2[i2]) {
|
|
i1++;
|
|
i2++;
|
|
}
|
|
return (ends_with_optional_cr(l1, s1, i1) &&
|
|
ends_with_optional_cr(l2, s2, i2));
|
|
}
|
|
|
|
/*
|
|
* After running out of one side, the remaining side must have
|
|
* nothing but whitespace for the lines to match. Note that
|
|
* ignore-whitespace-at-eol case may break out of the loop
|
|
* while there still are characters remaining on both lines.
|
|
*/
|
|
if (i1 < s1) {
|
|
while (i1 < s1 && XDL_ISSPACE(l1[i1]))
|
|
i1++;
|
|
if (s1 != i1)
|
|
return 0;
|
|
}
|
|
if (i2 < s2) {
|
|
while (i2 < s2 && XDL_ISSPACE(l2[i2]))
|
|
i2++;
|
|
return (s2 == i2);
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static unsigned long xdl_hash_record_with_whitespace(char const **data,
|
|
char const *top, long flags) {
|
|
unsigned long ha = 5381;
|
|
char const *ptr = *data;
|
|
int cr_at_eol_only = (flags & XDF_WHITESPACE_FLAGS) == XDF_IGNORE_CR_AT_EOL;
|
|
|
|
for (; ptr < top && *ptr != '\n'; ptr++) {
|
|
if (cr_at_eol_only) {
|
|
/* do not ignore CR at the end of an incomplete line */
|
|
if (*ptr == '\r' &&
|
|
(ptr + 1 < top && ptr[1] == '\n'))
|
|
continue;
|
|
}
|
|
else if (XDL_ISSPACE(*ptr)) {
|
|
const char *ptr2 = ptr;
|
|
int at_eol;
|
|
while (ptr + 1 < top && XDL_ISSPACE(ptr[1])
|
|
&& ptr[1] != '\n')
|
|
ptr++;
|
|
at_eol = (top <= ptr + 1 || ptr[1] == '\n');
|
|
if (flags & XDF_IGNORE_WHITESPACE)
|
|
; /* already handled */
|
|
else if (flags & XDF_IGNORE_WHITESPACE_CHANGE
|
|
&& !at_eol) {
|
|
ha += (ha << 5);
|
|
ha ^= (unsigned long) ' ';
|
|
}
|
|
else if (flags & XDF_IGNORE_WHITESPACE_AT_EOL
|
|
&& !at_eol) {
|
|
while (ptr2 != ptr + 1) {
|
|
ha += (ha << 5);
|
|
ha ^= (unsigned long) *ptr2;
|
|
ptr2++;
|
|
}
|
|
}
|
|
continue;
|
|
}
|
|
ha += (ha << 5);
|
|
ha ^= (unsigned long) *ptr;
|
|
}
|
|
*data = ptr < top ? ptr + 1: ptr;
|
|
|
|
return ha;
|
|
}
|
|
|
|
unsigned long xdl_hash_record(char const **data, char const *top, long flags) {
|
|
unsigned long ha = 5381;
|
|
char const *ptr = *data;
|
|
|
|
if (flags & XDF_WHITESPACE_FLAGS)
|
|
return xdl_hash_record_with_whitespace(data, top, flags);
|
|
|
|
for (; ptr < top && *ptr != '\n'; ptr++) {
|
|
ha += (ha << 5);
|
|
ha ^= (unsigned long) *ptr;
|
|
}
|
|
*data = ptr < top ? ptr + 1: ptr;
|
|
|
|
return ha;
|
|
}
|
|
|
|
unsigned int xdl_hashbits(unsigned int size) {
|
|
unsigned int val = 1, bits = 0;
|
|
|
|
for (; val < size && bits < CHAR_BIT * sizeof(unsigned int); val <<= 1, bits++);
|
|
return bits ? bits: 1;
|
|
}
|
|
|
|
|
|
int xdl_num_out(char *out, long val) {
|
|
char *ptr, *str = out;
|
|
char buf[32];
|
|
|
|
ptr = buf + sizeof(buf) - 1;
|
|
*ptr = '\0';
|
|
if (val < 0) {
|
|
*--ptr = '-';
|
|
val = -val;
|
|
}
|
|
for (; val && ptr > buf; val /= 10)
|
|
*--ptr = "0123456789"[val % 10];
|
|
if (*ptr)
|
|
for (; *ptr; ptr++, str++)
|
|
*str = *ptr;
|
|
else
|
|
*str++ = '0';
|
|
*str = '\0';
|
|
|
|
return str - out;
|
|
}
|
|
|
|
static int xdl_format_hunk_hdr(long s1, long c1, long s2, long c2,
|
|
const char *func, long funclen,
|
|
xdemitcb_t *ecb) {
|
|
int nb = 0;
|
|
mmbuffer_t mb;
|
|
char buf[128];
|
|
|
|
memcpy(buf, "@@ -", 4);
|
|
nb += 4;
|
|
|
|
nb += xdl_num_out(buf + nb, c1 ? s1: s1 - 1);
|
|
|
|
if (c1 != 1) {
|
|
memcpy(buf + nb, ",", 1);
|
|
nb += 1;
|
|
|
|
nb += xdl_num_out(buf + nb, c1);
|
|
}
|
|
|
|
memcpy(buf + nb, " +", 2);
|
|
nb += 2;
|
|
|
|
nb += xdl_num_out(buf + nb, c2 ? s2: s2 - 1);
|
|
|
|
if (c2 != 1) {
|
|
memcpy(buf + nb, ",", 1);
|
|
nb += 1;
|
|
|
|
nb += xdl_num_out(buf + nb, c2);
|
|
}
|
|
|
|
memcpy(buf + nb, " @@", 3);
|
|
nb += 3;
|
|
if (func && funclen) {
|
|
buf[nb++] = ' ';
|
|
if (funclen > sizeof(buf) - nb - 1)
|
|
funclen = sizeof(buf) - nb - 1;
|
|
memcpy(buf + nb, func, funclen);
|
|
nb += funclen;
|
|
}
|
|
buf[nb++] = '\n';
|
|
|
|
mb.ptr = buf;
|
|
mb.size = nb;
|
|
if (ecb->out_line(ecb->priv, &mb, 1) < 0)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
|
|
int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
|
|
const char *func, long funclen,
|
|
xdemitcb_t *ecb) {
|
|
if (!ecb->out_hunk)
|
|
return xdl_format_hunk_hdr(s1, c1, s2, c2, func, funclen, ecb);
|
|
if (ecb->out_hunk(ecb->priv,
|
|
c1 ? s1 : s1 - 1, c1,
|
|
c2 ? s2 : s2 - 1, c2,
|
|
func, funclen) < 0)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
|
|
int xdl_fall_back_diff(xdfenv_t *diff_env, xpparam_t const *xpp,
|
|
int line1, int count1, int line2, int count2)
|
|
{
|
|
/*
|
|
* This probably does not work outside Git, since
|
|
* we have a very simple mmfile structure.
|
|
*
|
|
* Note: ideally, we would reuse the prepared environment, but
|
|
* the libxdiff interface does not (yet) allow for diffing only
|
|
* ranges of lines instead of the whole files.
|
|
*/
|
|
mmfile_t subfile1, subfile2;
|
|
xdfenv_t env;
|
|
|
|
subfile1.ptr = (char *)diff_env->xdf1.recs[line1 - 1]->ptr;
|
|
subfile1.size = diff_env->xdf1.recs[line1 + count1 - 2]->ptr +
|
|
diff_env->xdf1.recs[line1 + count1 - 2]->size - subfile1.ptr;
|
|
subfile2.ptr = (char *)diff_env->xdf2.recs[line2 - 1]->ptr;
|
|
subfile2.size = diff_env->xdf2.recs[line2 + count2 - 2]->ptr +
|
|
diff_env->xdf2.recs[line2 + count2 - 2]->size - subfile2.ptr;
|
|
if (xdl_do_diff(&subfile1, &subfile2, xpp, &env) < 0)
|
|
return -1;
|
|
|
|
memcpy(diff_env->xdf1.rchg + line1 - 1, env.xdf1.rchg, count1);
|
|
memcpy(diff_env->xdf2.rchg + line2 - 1, env.xdf2.rchg, count2);
|
|
|
|
xdl_free_env(&env);
|
|
|
|
return 0;
|
|
}
|