git/alias.c
Jeff King ae021d8791 use skip_prefix to avoid magic numbers
It's a common idiom to match a prefix and then skip past it
with a magic number, like:

  if (starts_with(foo, "bar"))
	  foo += 3;

This is easy to get wrong, since you have to count the
prefix string yourself, and there's no compiler check if the
string changes.  We can use skip_prefix to avoid the magic
numbers here.

Note that some of these conversions could be much shorter.
For example:

  if (starts_with(arg, "--foo=")) {
	  bar = arg + 6;
	  continue;
  }

could become:

  if (skip_prefix(arg, "--foo=", &bar))
	  continue;

However, I have left it as:

  if (skip_prefix(arg, "--foo=", &v)) {
	  bar = v;
	  continue;
  }

to visually match nearby cases which need to actually
process the string. Like:

  if (skip_prefix(arg, "--foo=", &v)) {
	  bar = atoi(v);
	  continue;
  }

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-20 10:44:45 -07:00

90 lines
1.7 KiB
C

#include "cache.h"
static const char *alias_key;
static char *alias_val;
static int alias_lookup_cb(const char *k, const char *v, void *cb)
{
const char *name;
if (skip_prefix(k, "alias.", &name) && !strcmp(name, alias_key)) {
if (!v)
return config_error_nonbool(k);
alias_val = xstrdup(v);
return 0;
}
return 0;
}
char *alias_lookup(const char *alias)
{
alias_key = alias;
alias_val = NULL;
git_config(alias_lookup_cb, NULL);
return alias_val;
}
#define SPLIT_CMDLINE_BAD_ENDING 1
#define SPLIT_CMDLINE_UNCLOSED_QUOTE 2
static const char *split_cmdline_errors[] = {
"cmdline ends with \\",
"unclosed quote"
};
int split_cmdline(char *cmdline, const char ***argv)
{
int src, dst, count = 0, size = 16;
char quoted = 0;
*argv = xmalloc(sizeof(**argv) * size);
/* split alias_string */
(*argv)[count++] = cmdline;
for (src = dst = 0; cmdline[src];) {
char c = cmdline[src];
if (!quoted && isspace(c)) {
cmdline[dst++] = 0;
while (cmdline[++src]
&& isspace(cmdline[src]))
; /* skip */
ALLOC_GROW(*argv, count + 1, size);
(*argv)[count++] = cmdline + dst;
} else if (!quoted && (c == '\'' || c == '"')) {
quoted = c;
src++;
} else if (c == quoted) {
quoted = 0;
src++;
} else {
if (c == '\\' && quoted != '\'') {
src++;
c = cmdline[src];
if (!c) {
free(*argv);
*argv = NULL;
return -SPLIT_CMDLINE_BAD_ENDING;
}
}
cmdline[dst++] = c;
src++;
}
}
cmdline[dst] = 0;
if (quoted) {
free(*argv);
*argv = NULL;
return -SPLIT_CMDLINE_UNCLOSED_QUOTE;
}
ALLOC_GROW(*argv, count + 1, size);
(*argv)[count] = NULL;
return count;
}
const char *split_cmdline_strerror(int split_cmdline_errno)
{
return split_cmdline_errors[-split_cmdline_errno - 1];
}