git/config.c

547 строки
11 KiB
C

/*
* GIT - The information manager from hell
*
* Copyright (C) Linus Torvalds, 2005
* Copyright (C) Johannes Schindelin, 2005
*
*/
#include "cache.h"
#include <regex.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 == '\r') {
/* DOS like systems */
c = fgetc(f);
if (c != '\n') {
ungetc(c, f);
c = '\r';
}
}
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] = tolower(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;
}
if (!strcmp(var, "core.symrefsonly")) {
only_use_symrefs = git_config_bool(var, value);
return 0;
}
if (!strcmp(var, "user.name")) {
strncpy(git_default_name, value, sizeof(git_default_name));
return 0;
}
if (!strcmp(var, "user.email")) {
strncpy(git_default_email, value, sizeof(git_default_email));
return 0;
}
if (!strcmp(var, "diff.renamelimit")) {
diff_rename_limit_default = git_config_int(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;
}
/*
* Find all the stuff for git_config_set() below.
*/
static struct {
int baselen;
char* key;
regex_t* value_regex;
off_t offset;
enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
int seen;
} store;
static int store_aux(const char* key, const char* value)
{
switch (store.state) {
case KEY_SEEN:
if (!strcmp(key, store.key) &&
(store.value_regex == NULL ||
!regexec(store.value_regex, value, 0, NULL, 0))) {
if (store.seen == 1) {
fprintf(stderr,
"Warning: %s has multiple values\n",
key);
}
store.offset = ftell(config_file);
store.seen++;
}
break;
case SECTION_SEEN:
if (strncmp(key, store.key, store.baselen+1)) {
store.state = SECTION_END_SEEN;
break;
} else
store.offset = ftell(config_file);
/* fallthru */
case SECTION_END_SEEN:
case START:
if (!strcmp(key, store.key) &&
(store.value_regex == NULL ||
!regexec(store.value_regex, value, 0, NULL, 0))) {
store.offset = ftell(config_file);
store.state = KEY_SEEN;
store.seen++;
} else if(!strncmp(key, store.key, store.baselen))
store.state = SECTION_SEEN;
}
return 0;
}
static void store_write_section(int fd, const char* key)
{
write(fd, "[", 1);
write(fd, key, store.baselen);
write(fd, "]\n", 2);
}
static void store_write_pair(int fd, const char* key, const char* value)
{
int i;
write(fd, "\t", 1);
write(fd, key+store.baselen+1,
strlen(key+store.baselen+1));
write(fd, " = ", 3);
for (i = 0; value[i]; i++)
switch (value[i]) {
case '\n': write(fd, "\\n", 2); break;
case '\t': write(fd, "\\t", 2); break;
case '"': case '\\': write(fd, "\\", 1);
default: write(fd, value+i, 1);
}
write(fd, "\n", 1);
}
int git_config_set(const char* key, const char* value)
{
return git_config_set_multivar(key, value, NULL);
}
/*
* If value==NULL, unset in (remove from) config,
* if value_regex!=NULL, disregard key/value pairs where value does not match.
*
* Returns 0 on success.
*
* This function does this:
*
* - it locks the config file by creating ".git/config.lock"
*
* - it then parses the config using store_aux() as validator to find
* the position on the key/value pair to replace. If it is to be unset,
* it must be found exactly once.
*
* - the config file is mmap()ed and the part before the match (if any) is
* written to the lock file, then the changed part and the rest.
*
* - the config file is removed and the lock file rename()d to it.
*
*/
int git_config_set_multivar(const char* key, const char* value,
const char* value_regex)
{
int i;
struct stat st;
int fd;
char* config_file = strdup(git_path("config"));
char* lock_file = strdup(git_path("config.lock"));
/*
* Since "key" actually contains the section name and the real
* key name separated by a dot, we have to know where the dot is.
*/
for (store.baselen = 0;
key[store.baselen] != '.' && key[store.baselen];
store.baselen++);
if (!key[store.baselen] || !key[store.baselen+1]) {
fprintf(stderr, "key does not contain a section: %s\n", key);
return 2;
}
/*
* Validate the key and while at it, lower case it for matching.
*/
store.key = (char*)malloc(strlen(key)+1);
for (i = 0; key[i]; i++)
if (i != store.baselen && (!isalnum(key[i]) ||
(i == store.baselen+1 && !isalpha(key[i])))) {
fprintf(stderr, "invalid key: %s\n", key);
free(store.key);
return 1;
} else
store.key[i] = tolower(key[i]);
/*
* The lock_file serves a purpose in addition to locking: the new
* contents of .git/config will be written into it.
*/
fd = open(lock_file, O_WRONLY | O_CREAT | O_EXCL, 0666);
if (fd < 0) {
fprintf(stderr, "could not lock config file\n");
free(store.key);
return -1;
}
/*
* If .git/config does not exist yet, write a minimal version.
*/
if (stat(config_file, &st)) {
static const char contents[] =
"#\n"
"# This is the config file\n"
"#\n"
"\n";
free(store.key);
/* if nothing to unset, error out */
if (value == NULL) {
close(fd);
unlink(lock_file);
return 5;
}
store.key = (char*)key;
write(fd, contents, sizeof(contents)-1);
store_write_section(fd, key);
store_write_pair(fd, key, value);
} else{
int in_fd;
char* contents;
int offset, new_line = 0;
if (value_regex == NULL)
store.value_regex = NULL;
else {
store.value_regex = (regex_t*)malloc(sizeof(regex_t));
if (regcomp(store.value_regex, value_regex,
REG_EXTENDED)) {
fprintf(stderr, "Invalid pattern: %s",
value_regex);
free(store.value_regex);
return 6;
}
}
store.offset = 0;
store.state = START;
store.seen = 0;
/*
* After this, store.offset will contain the *end* offset
* of the last match, or remain at 0 if no match was found.
* As a side effect, we make sure to transform only a valid
* existing config file.
*/
if (git_config(store_aux)) {
fprintf(stderr, "invalid config file\n");
free(store.key);
if (store.value_regex != NULL) {
regfree(store.value_regex);
free(store.value_regex);
}
return 3;
}
free(store.key);
if (store.value_regex != NULL) {
regfree(store.value_regex);
free(store.value_regex);
}
/* if nothing to unset, error out */
if (store.seen == 0 && value == NULL) {
close(fd);
unlink(lock_file);
return 5;
}
store.key = (char*)key;
in_fd = open(config_file, O_RDONLY, 0666);
contents = mmap(NULL, st.st_size, PROT_READ,
MAP_PRIVATE, in_fd, 0);
close(in_fd);
if (store.offset == 0) {
store.offset = offset = st.st_size;
} else if (store.state != KEY_SEEN) {
offset = store.offset;
} else {
int equal_offset = st.st_size,
bracket_offset = st.st_size;
if (value == NULL && store.seen > 1) {
fprintf(stderr, "Cannot remove multivar (%s has %d values\n", key, store.seen);
close(fd);
unlink(lock_file);
return 7;
}
for (offset = store.offset-2; offset > 0
&& contents[offset] != '\n'; offset--)
switch (contents[offset]) {
case '=': equal_offset = offset; break;
case ']': bracket_offset = offset; break;
}
if (bracket_offset < equal_offset) {
new_line = 1;
offset = bracket_offset+1;
} else
offset++;
}
/* write the first part of the config */
write(fd, contents, offset);
if (new_line)
write(fd, "\n", 1);
/* write the pair (value == NULL means unset) */
if (value != NULL) {
if (store.state == START)
store_write_section(fd, key);
store_write_pair(fd, key, value);
}
/* write the rest of the config */
if (store.offset < st.st_size)
write(fd, contents + store.offset,
st.st_size - store.offset);
munmap(contents, st.st_size);
unlink(config_file);
}
close(fd);
if (rename(lock_file, config_file) < 0) {
fprintf(stderr, "Could not rename the lock file?\n");
return 4;
}
return 0;
}