git/config.c
Linus Torvalds 5cbb401dba Improve config file escape sanity checking
I had meant to disallow unknown escape characters in the config file
parser, but instead an unknown escaped character would silently pass
through as itself. That's correct for some cases (notably '\' itself), but
wasn't correct in general.

This fixes it, and makes the parser write a nice error message if the
config file contains bogus escaped characters.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2005-10-11 15:24:11 -07:00

228 lines
3.6 KiB
C

#include <ctype.h>
#include "cache.h"
#define MAXNAME (256)
static FILE *config_file;
static int config_linenr;
static int get_next_char(void)
{
int c;
FILE *f;
c = '\n';
if ((f = config_file) != NULL) {
c = fgetc(f);
if (c == '\n')
config_linenr++;
if (c == EOF) {
config_file = NULL;
c = '\n';
}
}
return c;
}
static char *parse_value(void)
{
static char value[1024];
int quote = 0, comment = 0, len = 0, space = 0;
for (;;) {
int c = get_next_char();
if (len >= sizeof(value))
return NULL;
if (c == '\n') {
if (quote)
return NULL;
value[len] = 0;
return value;
}
if (comment)
continue;
if (isspace(c) && !quote) {
space = 1;
continue;
}
if (space) {
if (len)
value[len++] = ' ';
space = 0;
}
if (c == '\\') {
c = get_next_char();
switch (c) {
case '\n':
continue;
case 't':
c = '\t';
break;
case 'b':
c = '\b';
break;
case 'n':
c = '\n';
break;
/* Some characters escape as themselves */
case '\\': case '"':
break;
/* Reject unknown escape sequences */
default:
return NULL;
}
value[len++] = c;
continue;
}
if (c == '"') {
quote = 1-quote;
continue;
}
if (!quote) {
if (c == ';' || c == '#') {
comment = 1;
continue;
}
}
value[len++] = c;
}
}
static int get_value(config_fn_t fn, char *name, unsigned int len)
{
int c;
char *value;
/* Get the full name */
for (;;) {
c = get_next_char();
if (c == EOF)
break;
if (!isalnum(c))
break;
name[len++] = tolower(c);
if (len >= MAXNAME)
return -1;
}
name[len] = 0;
while (c == ' ' || c == '\t')
c = get_next_char();
value = NULL;
if (c != '\n') {
if (c != '=')
return -1;
value = parse_value();
if (!value)
return -1;
}
return fn(name, value);
}
static int get_base_var(char *name)
{
int baselen = 0;
for (;;) {
int c = get_next_char();
if (c == EOF)
return -1;
if (c == ']')
return baselen;
if (!isalnum(c))
return -1;
if (baselen > MAXNAME / 2)
return -1;
name[baselen++] = tolower(c);
}
}
static int git_parse_file(config_fn_t fn)
{
int comment = 0;
int baselen = 0;
static char var[MAXNAME];
for (;;) {
int c = get_next_char();
if (c == '\n') {
/* EOF? */
if (!config_file)
return 0;
comment = 0;
continue;
}
if (comment || isspace(c))
continue;
if (c == '#' || c == ';') {
comment = 1;
continue;
}
if (c == '[') {
baselen = get_base_var(var);
if (baselen <= 0)
break;
var[baselen++] = '.';
var[baselen] = 0;
continue;
}
if (!isalpha(c))
break;
var[baselen] = c;
if (get_value(fn, var, baselen+1) < 0)
break;
}
die("bad config file line %d", config_linenr);
}
int git_config_int(const char *name, const char *value)
{
if (value && *value) {
char *end;
int val = strtol(value, &end, 0);
if (!*end)
return val;
}
die("bad config value for '%s'", name);
}
int git_config_bool(const char *name, const char *value)
{
if (!value)
return 1;
if (!*value)
return 0;
if (!strcasecmp(value, "true"))
return 1;
if (!strcasecmp(value, "false"))
return 0;
return git_config_int(name, value) != 0;
}
int git_default_config(const char *var, const char *value)
{
/* This needs a better name */
if (!strcmp(var, "core.filemode")) {
trust_executable_bit = git_config_bool(var, value);
return 0;
}
/* Add other config variables here.. */
return 0;
}
int git_config(config_fn_t fn)
{
int ret;
FILE *f = fopen(git_path("config"), "r");
ret = -1;
if (f) {
config_file = f;
config_linenr = 1;
ret = git_parse_file(fn);
fclose(f);
}
return ret;
}