git/xdiff-interface.c
Junio C Hamano f258475a6e Per-path attribute based hunk header selection.
This makes"diff -p" hunk headers customizable via gitattributes mechanism.
It is based on Johannes's earlier patch that allowed to define a single
regexp to be used for everything.

The mechanism to arrive at the regexp that is used to define hunk header
is the same as other use of gitattributes.  You assign an attribute, funcname
(because "diff -p" typically uses the name of the function the patch is about
as the hunk header), a simple string value.  This can be one of the names of
built-in pattern (currently, "java" is defined) or a custom pattern name, to
be looked up from the configuration file.

  (in .gitattributes)
  *.java   funcname=java
  *.perl   funcname=perl

  (in .git/config)
  [funcname]
    java = ... # ugly and complicated regexp to override the built-in one.
    perl = ... # another ugly and complicated regexp to define a new one.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-07-06 01:20:47 -07:00

203 lines
4.5 KiB
C

#include "cache.h"
#include "xdiff-interface.h"
static int parse_num(char **cp_p, int *num_p)
{
char *cp = *cp_p;
int num = 0;
int read_some;
while ('0' <= *cp && *cp <= '9')
num = num * 10 + *cp++ - '0';
if (!(read_some = cp - *cp_p))
return -1;
*cp_p = cp;
*num_p = num;
return 0;
}
int parse_hunk_header(char *line, int len,
int *ob, int *on,
int *nb, int *nn)
{
char *cp;
cp = line + 4;
if (parse_num(&cp, ob)) {
bad_line:
return error("malformed diff output: %s", line);
}
if (*cp == ',') {
cp++;
if (parse_num(&cp, on))
goto bad_line;
}
else
*on = 1;
if (*cp++ != ' ' || *cp++ != '+')
goto bad_line;
if (parse_num(&cp, nb))
goto bad_line;
if (*cp == ',') {
cp++;
if (parse_num(&cp, nn))
goto bad_line;
}
else
*nn = 1;
return -!!memcmp(cp, " @@", 3);
}
static void consume_one(void *priv_, char *s, unsigned long size)
{
struct xdiff_emit_state *priv = priv_;
char *ep;
while (size) {
unsigned long this_size;
ep = memchr(s, '\n', size);
this_size = (ep == NULL) ? size : (ep - s + 1);
priv->consume(priv, s, this_size);
size -= this_size;
s += this_size;
}
}
int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
{
struct xdiff_emit_state *priv = priv_;
int i;
for (i = 0; i < nbuf; i++) {
if (mb[i].ptr[mb[i].size-1] != '\n') {
/* Incomplete line */
priv->remainder = xrealloc(priv->remainder,
priv->remainder_size +
mb[i].size);
memcpy(priv->remainder + priv->remainder_size,
mb[i].ptr, mb[i].size);
priv->remainder_size += mb[i].size;
continue;
}
/* we have a complete line */
if (!priv->remainder) {
consume_one(priv, mb[i].ptr, mb[i].size);
continue;
}
priv->remainder = xrealloc(priv->remainder,
priv->remainder_size +
mb[i].size);
memcpy(priv->remainder + priv->remainder_size,
mb[i].ptr, mb[i].size);
consume_one(priv, priv->remainder,
priv->remainder_size + mb[i].size);
free(priv->remainder);
priv->remainder = NULL;
priv->remainder_size = 0;
}
if (priv->remainder) {
consume_one(priv, priv->remainder, priv->remainder_size);
free(priv->remainder);
priv->remainder = NULL;
priv->remainder_size = 0;
}
return 0;
}
int read_mmfile(mmfile_t *ptr, const char *filename)
{
struct stat st;
FILE *f;
size_t sz;
if (stat(filename, &st))
return error("Could not stat %s", filename);
if ((f = fopen(filename, "rb")) == NULL)
return error("Could not open %s", filename);
sz = xsize_t(st.st_size);
ptr->ptr = xmalloc(sz);
if (fread(ptr->ptr, sz, 1, f) != 1)
return error("Could not read %s", filename);
fclose(f);
ptr->size = sz;
return 0;
}
#define FIRST_FEW_BYTES 8000
int buffer_is_binary(const char *ptr, unsigned long size)
{
if (FIRST_FEW_BYTES < size)
size = FIRST_FEW_BYTES;
return !!memchr(ptr, 0, size);
}
struct ff_regs {
int nr;
struct ff_reg {
regex_t re;
int negate;
} *array;
};
static long ff_regexp(const char *line, long len,
char *buffer, long buffer_size, void *priv)
{
char *line_buffer = xstrndup(line, len); /* make NUL terminated */
struct ff_regs *regs = priv;
regmatch_t pmatch[2];
int result = 0, i;
for (i = 0; i < regs->nr; i++) {
struct ff_reg *reg = regs->array + i;
if (reg->negate ^ !!regexec(&reg->re,
line_buffer, 2, pmatch, 0)) {
free(line_buffer);
return -1;
}
}
i = pmatch[1].rm_so >= 0 ? 1 : 0;
line += pmatch[i].rm_so;
result = pmatch[i].rm_eo - pmatch[i].rm_so;
if (result > buffer_size)
result = buffer_size;
else
while (result > 0 && (isspace(line[result - 1]) ||
line[result - 1] == '\n'))
result--;
memcpy(buffer, line, result);
free(line_buffer);
return result;
}
void xdiff_set_find_func(xdemitconf_t *xecfg, const char *value)
{
int i;
struct ff_regs *regs;
xecfg->find_func = ff_regexp;
regs = xecfg->find_func_priv = xmalloc(sizeof(struct ff_regs));
for (i = 0, regs->nr = 1; value[i]; i++)
if (value[i] == '\n')
regs->nr++;
regs->array = xmalloc(regs->nr * sizeof(struct ff_reg));
for (i = 0; i < regs->nr; i++) {
struct ff_reg *reg = regs->array + i;
const char *ep = strchr(value, '\n'), *expression;
char *buffer = NULL;
reg->negate = (*value == '!');
if (reg->negate && i == regs->nr - 1)
die("Last expression must not be negated: %s", value);
if (*value == '!')
value++;
if (ep)
expression = buffer = xstrndup(value, ep - value);
else
expression = value;
if (regcomp(&reg->re, expression, 0))
die("Invalid regexp to look for hunk header: %s", expression);
if (buffer)
free(buffer);
value = ep + 1;
}
}