git-commit-vandalism/line-range.c
Bo Yang 25ed3412f8 Refactor parse_loc
We want to use the same style of -L n,m argument for 'git log -L' as
for git-blame.  Refactor the argument parsing of the range arguments
from builtin/blame.c to the (new) file that will hold the 'git log -L'
logic.

To accommodate different data structures in blame and log -L, the file
contents are abstracted away; parse_range_arg takes a callback that it
uses to get the contents of a line of the (notional) file.

The new test is for a case that made me pause during debugging: the
'blame -L with invalid end' test was the only one that noticed an
outright failure to parse the end *at all*.  So make a more explicit
test for that.

Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-03-28 10:28:41 -07:00

93 lines
2.0 KiB
C

#include "git-compat-util.h"
#include "line-range.h"
/*
* Parse one item in the -L option
*/
static const char *parse_loc(const char *spec, nth_line_fn_t nth_line,
void *data, long lines, long begin, long *ret)
{
char *term;
const char *line;
long num;
int reg_error;
regex_t regexp;
regmatch_t match[1];
/* Allow "-L <something>,+20" to mean starting at <something>
* for 20 lines, or "-L <something>,-5" for 5 lines ending at
* <something>.
*/
if (1 < begin && (spec[0] == '+' || spec[0] == '-')) {
num = strtol(spec + 1, &term, 10);
if (term != spec + 1) {
if (spec[0] == '-')
num = 0 - num;
if (0 < num)
*ret = begin + num - 2;
else if (!num)
*ret = begin;
else
*ret = begin + num;
return term;
}
return spec;
}
num = strtol(spec, &term, 10);
if (term != spec) {
*ret = num;
return term;
}
if (spec[0] != '/')
return spec;
/* it could be a regexp of form /.../ */
for (term = (char *) spec + 1; *term && *term != '/'; term++) {
if (*term == '\\')
term++;
}
if (*term != '/')
return spec;
/* try [spec+1 .. term-1] as regexp */
*term = 0;
begin--; /* input is in human terms */
line = nth_line(data, begin);
if (!(reg_error = regcomp(&regexp, spec + 1, REG_NEWLINE)) &&
!(reg_error = regexec(&regexp, line, 1, match, 0))) {
const char *cp = line + match[0].rm_so;
const char *nline;
while (begin++ < lines) {
nline = nth_line(data, begin);
if (line <= cp && cp < nline)
break;
line = nline;
}
*ret = begin;
regfree(&regexp);
*term++ = '/';
return term;
}
else {
char errbuf[1024];
regerror(reg_error, &regexp, errbuf, 1024);
die("-L parameter '%s': %s", spec + 1, errbuf);
}
}
int parse_range_arg(const char *arg, nth_line_fn_t nth_line_cb,
void *cb_data, long lines, long *begin, long *end)
{
arg = parse_loc(arg, nth_line_cb, cb_data, lines, 1, begin);
if (*arg == ',')
arg = parse_loc(arg + 1, nth_line_cb, cb_data, lines, *begin + 1, end);
if (*arg)
return -1;
return 0;
}