/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#include "common.h"
#include "config.h"
#include "filebuf.h"
#include "sysdir.h"
#include "buffer.h"
#include "buf_text.h"
#include "git2/config.h"
#include "git2/sys/config.h"
#include "git2/types.h"
#include "strmap.h"
#include "array.h"
#include <ctype.h>
#include <sys/types.h>
#include <regex.h>
typedef struct cvar_t {
struct cvar_t *next;
git_config_entry *entry;
bool included; /* whether this is part of [include] */
} cvar_t;
typedef struct git_config_file_iter {
git_config_iterator parent;
git_strmap_iter iter;
cvar_t* next_var;
} git_config_file_iter;
/* Max depth for [include] directives */
#define MAX_INCLUDE_DEPTH 10
#define CVAR_LIST_HEAD(list) ((list)->head)
#define CVAR_LIST_TAIL(list) ((list)->tail)
#define CVAR_LIST_NEXT(var) ((var)->next)
#define CVAR_LIST_EMPTY(list) ((list)->head == NULL)
#define CVAR_LIST_APPEND(list, var) do {\
if (CVAR_LIST_EMPTY(list)) {\
CVAR_LIST_HEAD(list) = CVAR_LIST_TAIL(list) = var;\
} else {\
CVAR_LIST_NEXT(CVAR_LIST_TAIL(list)) = var;\
CVAR_LIST_TAIL(list) = var;\
}\
} while(0)
#define CVAR_LIST_REMOVE_HEAD(list) do {\
CVAR_LIST_HEAD(list) = CVAR_LIST_NEXT(CVAR_LIST_HEAD(list));\
} while(0)
#define CVAR_LIST_REMOVE_AFTER(var) do {\
CVAR_LIST_NEXT(var) = CVAR_LIST_NEXT(CVAR_LIST_NEXT(var));\
} while(0)
#define CVAR_LIST_FOREACH(list, iter)\
for ((iter) = CVAR_LIST_HEAD(list);\
(iter) != NULL;\
(iter) = CVAR_LIST_NEXT(iter))
/*
* Inspired by the FreeBSD functions
*/
#define CVAR_LIST_FOREACH_SAFE(start, iter, tmp)\
for ((iter) = CVAR_LIST_HEAD(vars);\
(iter) && (((tmp) = CVAR_LIST_NEXT(iter) || 1));\
(iter) = (tmp))
struct reader {
git_oid checksum;
char *file_path;
git_buf buffer;
char *read_ptr;
int line_number;
int eof;
};
typedef struct {
git_atomic refcount;
git_strmap *values;
} refcounted_strmap;
typedef struct {
git_config_backend parent;
/* mutex to coordinate accessing the values */
git_mutex values_mutex;
refcounted_strmap *values;
} diskfile_header;
typedef struct {
diskfile_header header;
git_config_level_t level;
git_array_t(struct reader) readers;
bool locked;
git_filebuf locked_buf;
git_buf locked_content;
char *file_path;
} diskfile_backend;
typedef struct {
diskfile_header header;
diskfile_backend *snapshot_from;
} diskfile_readonly_backend;
static int config_read(git_strmap *values, diskfile_backend *cfg_file, struct reader *reader, git_config_level_t level, int depth);
static int config_write(diskfile_backend *cfg, const char *key, const regex_t *preg, const char *value);
static char *escape_value(const char *ptr);
int git_config_file__snapshot(git_config_backend **out, diskfile_backend *in);
static int config_snapshot(git_config_backend **out, git_config_backend *in);
static void set_parse_error(struct reader *reader, int col, const char *error_str)
{
giterr_set(GITERR_CONFIG, "failed to parse config file: %s (in %s:%d, column %d)",
error_str, reader->file_path, reader->line_number, col);
}
static int config_error_readonly(void)
{
giterr_set(GITERR_CONFIG, "this backend is read-only");
return -1;
}
static void cvar_free(cvar_t *var)
{
if (var == NULL)
return;
git__free((char*)var->entry->name);
git__free((char *)var->entry->value);
git__free(var->entry);
git__free(var);
}
int git_config_file_normalize_section(char *start, char *end)
{
char *scan;
if (start == end)
return GIT_EINVALIDSPEC;
/* Validate and downcase range */
for (scan = start; *scan; ++scan) {
if (end && scan >= end)
break;
if (isalnum(*scan))
*scan = (char)git__tolower(*scan);
else if (*scan != '-' || scan == start)
return GIT_EINVALIDSPEC;
}
if (scan == start)
return GIT_EINVALIDSPEC;
return 0;
}
/* Add or append the new config option */
static int append_entry(git_strmap *values, cvar_t *var)
{
git_strmap_iter pos;
cvar_t *existing;
int error = 0;
pos = git_strmap_lookup_index(values, var->entry->name);
if (!git_strmap_valid_index(values, pos)) {
git_strmap_insert(values, var->entry->name, var, &error);
} else {
existing = git_strmap_value_at(values, pos);
while (existing->next != NULL) {
existing = existing->next;
}
existing->next = var;
}
if (error > 0)
error = 0;
return error;
}
static void free_vars(git_strmap *values)
{
cvar_t *var = NULL;
if (values == NULL)
return;
git_strmap_foreach_value(values, var,
while (var != NULL) {
cvar_t *next = CVAR_LIST_NEXT(var);
cvar_free(var);
var = next;
});
git_strmap_free(values);
}
static void refcounted_strmap_free(refcounted_strmap *map)
{
if (!map)
return;
if (git_atomic_dec(&map->refcount) != 0)
return;
free_vars(map->values);
git__free(map);
}
/**
* Take the current values map from the backend and increase its
* refcount. This is its own function to make sure we use the mutex to
* avoid the map pointer from changing under us.
*/
static refcounted_strmap *refcounted_strmap_take(diskfile_header *h)
{
refcounted_strmap *map;
if (git_mutex_lock(&h->values_mutex) < 0) {
giterr_set(GITERR_OS, "failed to lock config backend");
return NULL;
}
map = h->values;
git_atomic_inc(&map->refcount);
git_mutex_unlock(&h->values_mutex);
return map;
}
static int refcounted_strmap_alloc(refcounted_strmap **out)
{
refcounted_strmap *map;
int error;
map = git__calloc(1, sizeof(refcounted_strmap));
GITERR_CHECK_ALLOC(map);
git_atomic_set(&map->refcount, 1);
if ((error = git_strmap_alloc(&map->values)) < 0)
git__free(map);
else
*out = map;
return error;
}
static int config_open(git_config_backend *cfg, git_config_level_t level)
{
int res;
struct reader *reader;
diskfile_backend *b = (diskfile_backend *)cfg;
b->level = level;
if ((res = refcounted_strmap_alloc(&b->header.values)) < 0)
return res;
git_array_init(b->readers);
reader = git_array_alloc(b->readers);
if (!reader) {
refcounted_strmap_free(b->header.values);
return -1;
}
memset(reader, 0, sizeof(struct reader));
reader->file_path = git__strdup(b->file_path);
GITERR_CHECK_ALLOC(reader->file_path);
git_buf_init(&reader->buffer, 0);
res = git_futils_readbuffer_updated(
&reader->buffer, b->file_path, &reader->checksum, NULL);
/* It's fine if the file doesn't exist */
if (res == GIT_ENOTFOUND)
return 0;
if (res < 0 || (res = config_read(b->header.values->values, b, reader, level, 0)) < 0) {
refcounted_strmap_free(b->header.values);
b->header.values = NULL;
}
reader = git_array_get(b->readers, 0);
git_buf_free(&reader->buffer);
return res;
}
/* The meat of the refresh, as we want to use it in different places */
static int config__refresh(git_config_backend *cfg)
{
refcounted_strmap *values = NULL, *tmp;
diskfile_backend *b = (diskfile_backend *)cfg;
struct reader *reader = NULL;
int error = 0;
if ((error = refcounted_strmap_alloc(&values)) < 0)
goto out;
reader = git_array_get(b->readers, git_array_size(b->readers) - 1);
GITERR_CHECK_ALLOC(reader);
if ((error = config_read(values->values, b, reader, b->level, 0)) < 0)
goto out;
if ((error = git_mutex_lock(&b->header.values_mutex)) < 0) {
giterr_set(GITERR_OS, "failed to lock config backend");
goto out;
}
tmp = b->header.values;
b->header.values = values;
values = tmp;
git_mutex_unlock(&b->header.values_mutex);
out:
refcounted_strmap_free(values);
if (reader)
git_buf_free(&reader->buffer);
return error;
}
static int config_refresh(git_config_backend *cfg)
{
int error = 0, updated = 0, any_updated = 0;
diskfile_backend *b = (diskfile_backend *)cfg;
struct reader *reader = NULL;
uint32_t i;
for (i = 0; i < git_array_size(b->readers); i++) {
reader = git_array_get(b->readers, i);
error = git_futils_readbuffer_updated(
&reader->buffer, reader->file_path,
&reader->checksum, &updated);
if (error < 0 && error != GIT_ENOTFOUND)
return error;
if (updated)
any_updated = 1;
}
if (!any_updated)
return (error == GIT_ENOTFOUND) ? 0 : error;
return config__refresh(cfg);
}
static void backend_free(git_config_backend *_backend)
{
diskfile_backend *backend = (diskfile_backend *)_backend;
uint32_t i;
if (backend == NULL)
return;
for (i = 0; i < git_array_size(backend->readers); i++) {
struct reader *r = git_array_get(backend->readers, i);
git__free(r->file_path);
}
git_array_clear(backend->readers);
git__free(backend->file_path);
refcounted_strmap_free(backend->header.values);
git_mutex_free(&backend->header.values_mutex);
git__free(backend);
}
static void config_iterator_free(
git_config_iterator* iter)
{
iter->backend->free(iter->backend);
git__free(iter);
}
static int config_iterator_next(
git_config_entry **entry,
git_config_iterator *iter)
{
git_config_file_iter *it = (git_config_file_iter *) iter;
diskfile_header *h = (diskfile_header *) it->parent.backend;
git_strmap *values = h->values->values;
int err = 0;
cvar_t * var;
if (it->next_var == NULL) {
err = git_strmap_next((void**) &var, &(it->iter), values);
} else {
var = it->next_var;
}
if (err < 0) {
it->next_var = NULL;
return err;
}
*entry = var->entry;
it->next_var = CVAR_LIST_NEXT(var);
return 0;
}
static int config_iterator_new(
git_config_iterator **iter,
struct git_config_backend* backend)
{
diskfile_header *h;
git_config_file_iter *it;
git_config_backend *snapshot;
diskfile_backend *b = (diskfile_backend *) backend;
int error;
if ((error = config_snapshot(&snapshot, backend)) < 0)
return error;
if ((error = snapshot->open(snapshot, b->level)) < 0)
return error;
it = git__calloc(1, sizeof(git_config_file_iter));
GITERR_CHECK_ALLOC(it);
h = (diskfile_header *)snapshot;
/* strmap_begin() is currently a macro returning 0 */
GIT_UNUSED(h);
it->parent.backend = snapshot;
it->iter = git_strmap_begin(h->values);
it->next_var = NULL;
it->parent.next = config_iterator_next;
it->parent.free = config_iterator_free;
*iter = (git_config_iterator *) it;
return 0;
}
static int config_set(git_config_backend *cfg, const char *name, const char *value)
{
diskfile_backend *b = (diskfile_backend *)cfg;
refcounted_strmap *map;
git_strmap *values;
char *key, *esc_value = NULL;
khiter_t pos;
int rval, ret;
if ((rval = git_config__normalize_name(name, &key)) < 0)
return rval;
if ((map = refcounted_strmap_take(&b->header)) == NULL)
return -1;
values = map->values;
/*
* Try to find it in the existing values and update it if it
* only has one value.
*/
pos = git_strmap_lookup_index(values, key);
if (git_strmap_valid_index(values, pos)) {
cvar_t *existing = git_strmap_value_at(values, pos);
if (existing->next != NULL) {
giterr_set(GITERR_CONFIG, "multivar incompatible with simple set");
ret = -1;
goto out;
}
/* don't update if old and new values already match */
if ((!existing->entry->value && !value) ||
(existing->entry->value && value &&
!strcmp(existing->entry->value, value))) {
ret = 0;
goto out;
}
}
/* No early returns due to sanity checks, let's write it out and refresh */
if (value) {
esc_value = escape_value(value);
GITERR_CHECK_ALLOC(esc_value);
}
if ((ret = config_write(b, key, NULL, esc_value)) < 0)
goto out;
ret = config_refresh(cfg);
out:
refcounted_strmap_free(map);
git__free(esc_value);
git__free(key);
return ret;
}
/* release the map containing the entry as an equivalent to freeing it */
static void release_map(git_config_entry *entry)
{
refcounted_strmap *map = (refcounted_strmap *) entry->payload;
refcounted_strmap_free(map);
}
/*
* Internal function that actually gets the value in string form
*/
static int config_get(git_config_backend *cfg, const char *key, git_config_entry **out)
{
diskfile_header *h = (diskfile_header *)cfg;
refcounted_strmap *map;
git_strmap *values;
khiter_t pos;
cvar_t *var;
int error = 0;
if (!h->parent.readonly && ((error = config_refresh(cfg)) < 0))
return error;
if ((map = refcounted_strmap_take(h)) == NULL)
return -1;
values = map->values;
pos = git_strmap_lookup_index(values, key);
/* no error message; the config system will write one */
if (!git_strmap_valid_index(values, pos)) {
refcounted_strmap_free(map);
return GIT_ENOTFOUND;
}
var = git_strmap_value_at(values, pos);
while (var->next)
var = var->next;
*out = var->entry;
(*out)->free = release_map;
(*out)->payload = map;
return error;
}
static int config_set_multivar(
git_config_backend *cfg, const char *name, const char *regexp, const char *value)
{
diskfile_backend *b = (diskfile_backend *)cfg;
char *key;
regex_t preg;
int result;
assert(regexp);
if ((result = git_config__normalize_name(name, &key)) < 0)
return result;
result = p_regcomp(&preg, regexp, REG_EXTENDED);
if (result != 0) {
giterr_set_regex(&preg, result);
result = -1;
goto out;
}
/* If we do have it, set call config_write() and reload */
if ((result = config_write(b, key, &preg, value)) < 0)
goto out;
result = config_refresh(cfg);
out:
git__free(key);
regfree(&preg);
return result;
}
static int config_delete(git_config_backend *cfg, const char *name)
{
cvar_t *var;
diskfile_backend *b = (diskfile_backend *)cfg;
refcounted_strmap *map; git_strmap *values;
char *key;
int result;
khiter_t pos;
if ((result = git_config__normalize_name(name, &key)) < 0)
return result;
if ((map = refcounted_strmap_take(&b->header)) == NULL)
return -1;
values = b->header.values->values;
pos = git_strmap_lookup_index(values, key);
git__free(key);
if (!git_strmap_valid_index(values, pos)) {
refcounted_strmap_free(map);
giterr_set(GITERR_CONFIG, "could not find key '%s' to delete", name);
return GIT_ENOTFOUND;
}
var = git_strmap_value_at(values, pos);
refcounted_strmap_free(map);
if (var->next != NULL) {
giterr_set(GITERR_CONFIG, "cannot delete multivar with a single delete");
return -1;
}
if ((result = config_write(b, var->entry->name, NULL, NULL)) < 0)
return result;
return config_refresh(cfg);
}
static int config_delete_multivar(git_config_backend *cfg, const char *name, const char *regexp)
{
diskfile_backend *b = (diskfile_backend *)cfg;
refcounted_strmap *map;
git_strmap *values;
char *key;
regex_t preg;
int result;
khiter_t pos;
if ((result = git_config__normalize_name(name, &key)) < 0)
return result;
if ((map = refcounted_strmap_take(&b->header)) == NULL)
return -1;
values = b->header.values->values;
pos = git_strmap_lookup_index(values, key);
if (!git_strmap_valid_index(values, pos)) {
refcounted_strmap_free(map);
git__free(key);
giterr_set(GITERR_CONFIG, "could not find key '%s' to delete", name);
return GIT_ENOTFOUND;
}
refcounted_strmap_free(map);
result = p_regcomp(&preg, regexp, REG_EXTENDED);
if (result != 0) {
giterr_set_regex(&preg, result);
result = -1;
goto out;
}
if ((result = config_write(b, key, &preg, NULL)) < 0)
goto out;
result = config_refresh(cfg);
out:
git__free(key);
regfree(&preg);
return result;
}
static int config_snapshot(git_config_backend **out, git_config_backend *in)
{
diskfile_backend *b = (diskfile_backend *) in;
return git_config_file__snapshot(out, b);
}
static int config_lock(git_config_backend *_cfg)
{
diskfile_backend *cfg = (diskfile_backend *) _cfg;
int error;
if ((error = git_filebuf_open(&cfg->locked_buf, cfg->file_path, 0, GIT_CONFIG_FILE_MODE)) < 0)
return error;
error = git_futils_readbuffer(&cfg->locked_content, cfg->file_path);
if (error < 0 && error != GIT_ENOTFOUND) {
git_filebuf_cleanup(&cfg->locked_buf);
return error;
}
cfg->locked = true;
return 0;
}
static int config_unlock(git_config_backend *_cfg, int success)
{
diskfile_backend *cfg = (diskfile_backend *) _cfg;
int error = 0;
if (success) {
git_filebuf_write(&cfg->locked_buf, cfg->locked_content.ptr, cfg->locked_content.size);
error = git_filebuf_commit(&cfg->locked_buf);
}
git_filebuf_cleanup(&cfg->locked_buf);
git_buf_free(&cfg->locked_content);
cfg->locked = false;
return error;
}
int git_config_file__ondisk(git_config_backend **out, const char *path)
{
diskfile_backend *backend;
backend = git__calloc(1, sizeof(diskfile_backend));
GITERR_CHECK_ALLOC(backend);
backend->header.parent.version = GIT_CONFIG_BACKEND_VERSION;
git_mutex_init(&backend->header.values_mutex);
backend->file_path = git__strdup(path);
GITERR_CHECK_ALLOC(backend->file_path);
backend->header.parent.open = config_open;
backend->header.parent.get = config_get;
backend->header.parent.set = config_set;
backend->header.parent.set_multivar = config_set_multivar;
backend->header.parent.del = config_delete;
backend->header.parent.del_multivar = config_delete_multivar;
backend->header.parent.iterator = config_iterator_new;
backend->header.parent.snapshot = config_snapshot;
backend->header.parent.lock = config_lock;
backend->header.parent.unlock = config_unlock;
backend->header.parent.free = backend_free;
*out = (git_config_backend *)backend;
return 0;
}
static int config_set_readonly(git_config_backend *cfg, const char *name, const char *value)
{
GIT_UNUSED(cfg);
GIT_UNUSED(name);
GIT_UNUSED(value);
return config_error_readonly();
}
static int config_set_multivar_readonly(
git_config_backend *cfg, const char *name, const char *regexp, const char *value)
{
GIT_UNUSED(cfg);
GIT_UNUSED(name);
GIT_UNUSED(regexp);
GIT_UNUSED(value);
return config_error_readonly();
}
static int config_delete_multivar_readonly(git_config_backend *cfg, const char *name, const char *regexp)
{
GIT_UNUSED(cfg);
GIT_UNUSED(name);
GIT_UNUSED(regexp);
return config_error_readonly();
}
static int config_delete_readonly(git_config_backend *cfg, const char *name)
{
GIT_UNUSED(cfg);
GIT_UNUSED(name);
return config_error_readonly();
}
static int config_lock_readonly(git_config_backend *_cfg)
{
GIT_UNUSED(_cfg);
return config_error_readonly();
}
static int config_unlock_readonly(git_config_backend *_cfg, int success)
{
GIT_UNUSED(_cfg);
GIT_UNUSED(success);
return config_error_readonly();
}
static void backend_readonly_free(git_config_backend *_backend)
{
diskfile_backend *backend = (diskfile_backend *)_backend;
if (backend == NULL)
return;
refcounted_strmap_free(backend->header.values);
git_mutex_free(&backend->header.values_mutex);
git__free(backend);
}
static int config_readonly_open(git_config_backend *cfg, git_config_level_t level)
{
diskfile_readonly_backend *b = (diskfile_readonly_backend *) cfg;
diskfile_backend *src = b->snapshot_from;
diskfile_header *src_header = &src->header;
refcounted_strmap *src_map;
int error;
if (!src_header->parent.readonly && (error = config_refresh(&src_header->parent)) < 0)
return error;
/* We're just copying data, don't care about the level */
GIT_UNUSED(level);
if ((src_map = refcounted_strmap_take(src_header)) == NULL)
return -1;
b->header.values = src_map;
return 0;
}
int git_config_file__snapshot(git_config_backend **out, diskfile_backend *in)
{
diskfile_readonly_backend *backend;
backend = git__calloc(1, sizeof(diskfile_readonly_backend));
GITERR_CHECK_ALLOC(backend);
backend->header.parent.version = GIT_CONFIG_BACKEND_VERSION;
git_mutex_init(&backend->header.values_mutex);
backend->snapshot_from = in;
backend->header.parent.readonly = 1;
backend->header.parent.version = GIT_CONFIG_BACKEND_VERSION;
backend->header.parent.open = config_readonly_open;
backend->header.parent.get = config_get;
backend->header.parent.set = config_set_readonly;
backend->header.parent.set_multivar = config_set_multivar_readonly;
backend->header.parent.del = config_delete_readonly;
backend->header.parent.del_multivar = config_delete_multivar_readonly;
backend->header.parent.iterator = config_iterator_new;
backend->header.parent.lock = config_lock_readonly;
backend->header.parent.unlock = config_unlock_readonly;
backend->header.parent.free = backend_readonly_free;
*out = (git_config_backend *)backend;
return 0;
}
static int reader_getchar_raw(struct reader *reader)
{
int c;
c = *reader->read_ptr++;
/*
Win 32 line breaks: if we find a \r\n sequence,
return only the \n as a newline
*/
if (c == '\r' && *reader->read_ptr == '\n') {
reader->read_ptr++;
c = '\n';
}
if (c == '\n')
reader->line_number++;
if (c == 0) {
reader->eof = 1;
c = '\0';
}
return c;
}
#define SKIP_WHITESPACE (1 << 1)
#define SKIP_COMMENTS (1 << 2)
static int reader_getchar(struct reader *reader, int flags)
{
const int skip_whitespace = (flags & SKIP_WHITESPACE);
const int skip_comments = (flags & SKIP_COMMENTS);
int c;
assert(reader->read_ptr);
do {
c = reader_getchar_raw(reader);
} while (c != '\n' && c != '\0' && skip_whitespace && git__isspace(c));
if (skip_comments && (c == '#' || c == ';')) {
do {
c = reader_getchar_raw(reader);
} while (c != '\n' && c != '\0');
}
return c;
}
/*
* Read the next char, but don't move the reading pointer.
*/
static int reader_peek(struct reader *reader, int flags)
{
void *old_read_ptr;
int old_lineno, old_eof;
int ret;
assert(reader->read_ptr);
old_read_ptr = reader->read_ptr;
old_lineno = reader->line_number;
old_eof = reader->eof;
ret = reader_getchar(reader, flags);
reader->read_ptr = old_read_ptr;
reader->line_number = old_lineno;
reader->eof = old_eof;
return ret;
}
/*
* Read and consume a line, returning it in newly-allocated memory.
*/
static char *reader_readline(struct reader *reader, bool skip_whitespace)
{
char *line = NULL;
char *line_src, *line_end;
size_t line_len, alloc_len;
line_src = reader->read_ptr;
if (skip_whitespace) {
/* Skip empty empty lines */
while (git__isspace(*line_src))
++line_src;
}
line_end = strchr(line_src, '\n');
/* no newline at EOF */
if (line_end == NULL)
line_end = strchr(line_src, 0);
line_len = line_end - line_src;
if (GIT_ADD_SIZET_OVERFLOW(&alloc_len, line_len, 1) ||
(line = git__malloc(alloc_len)) == NULL) {
return NULL;
}
memcpy(line, line_src, line_len);
do line[line_len] = '\0';
while (line_len-- > 0 && git__isspace(line[line_len]));
if (*line_end == '\n')
line_end++;
if (*line_end == '\0')
reader->eof = 1;
reader->line_number++;
reader->read_ptr = line_end;
return line;
}
/*
* Consume a line, without storing it anywhere
*/
static void reader_consume_line(struct reader *reader)
{
char *line_start, *line_end;
line_start = reader->read_ptr;
line_end = strchr(line_start, '\n');
/* No newline at EOF */
if(line_end == NULL){
line_end = strchr(line_start, '\0');
}
if (*line_end == '\n')
line_end++;
if (*line_end == '\0')
reader->eof = 1;
reader->line_number++;
reader->read_ptr = line_end;
}
GIT_INLINE(int) config_keychar(int c)
{
return isalnum(c) || c == '-';
}
static int parse_section_header_ext(struct reader *reader, const char *line, const char *base_name, char **section_name)
{
int c, rpos;
char *first_quote, *last_quote;
git_buf buf = GIT_BUF_INIT;
size_t quoted_len, alloc_len, base_name_len = strlen(base_name);
/*
* base_name is what came before the space. We should be at the
* first quotation mark, except for now, line isn't being kept in
* sync so we only really use it to calculate the length.
*/
first_quote = strchr(line, '"');
if (first_quote == NULL) {
set_parse_error(reader, 0, "Missing quotation marks in section header");
goto end_error;
}
last_quote = strrchr(line, '"');
quoted_len = last_quote - first_quote;
if (quoted_len == 0) {
set_parse_error(reader, 0, "Missing closing quotation mark in section header");
goto end_error;
}
GITERR_CHECK_ALLOC_ADD(&alloc_len, base_name_len, quoted_len);
GITERR_CHECK_ALLOC_ADD(&alloc_len, alloc_len, 2);
if (git_buf_grow(&buf, alloc_len) < 0 ||
git_buf_printf(&buf, "%s.", base_name) < 0)
goto end_error;
rpos = 0;
line = first_quote;
c = line[++rpos];
/*
* At the end of each iteration, whatever is stored in c will be
* added to the string. In case of error, jump to out
*/
do {
switch (c) {
case 0:
set_parse_error(reader, 0, "Unexpected end-of-line in section header");
goto end_error;
case '"':
goto end_parse;
case '\\':
c = line[++rpos];
if (c == 0) {
set_parse_error(reader, rpos, "Unexpected end-of-line in section header");
goto end_error;
}
default:
break;
}
git_buf_putc(&buf, (char)c);
c = line[++rpos];
} while (line + rpos < last_quote);
end_parse:
if (git_buf_oom(&buf))
goto end_error;
if (line[rpos] != '"' || line[rpos + 1] != ']') {
set_parse_error(reader, rpos, "Unexpected text after closing quotes");
git_buf_free(&buf);
return -1;
}
*section_name = git_buf_detach(&buf);
return 0;
end_error:
git_buf_free(&buf);
return -1;
}
static int parse_section_header(struct reader *reader, char **section_out)
{
char *name, *name_end;
int name_length, c, pos;
int result;
char *line;
size_t line_len;
line = reader_readline(reader, true);
if (line == NULL)
return -1;
/* find the end of the variable's name */
name_end = strrchr(line, ']');
if (name_end == NULL) {
git__free(line);
set_parse_error(reader, 0, "Missing ']' in section header");
return -1;
}
GITERR_CHECK_ALLOC_ADD(&line_len, (size_t)(name_end - line), 1);
name = git__malloc(line_len);
GITERR_CHECK_ALLOC(name);
name_length = 0;
pos = 0;
/* Make sure we were given a section header */
c = line[pos++];
assert(c == '[');
c = line[pos++];
do {
if (git__isspace(c)){
name[name_length] = '\0';
result = parse_section_header_ext(reader, line, name, section_out);
git__free(line);
git__free(name);
return result;
}
if (!config_keychar(c) && c != '.') {
set_parse_error(reader, pos, "Unexpected character in header");
goto fail_parse;
}
name[name_length++] = (char)git__tolower(c);
} while ((c = line[pos++]) != ']');
if (line[pos - 1] != ']') {
set_parse_error(reader, pos, "Unexpected end of file");
goto fail_parse;
}
git__free(line);
name[name_length] = 0;
*section_out = name;
return 0;
fail_parse:
git__free(line);
git__free(name);
return -1;
}
static int skip_bom(struct reader *reader)
{
git_bom_t bom;
int bom_offset = git_buf_text_detect_bom(&bom,
&reader->buffer, reader->read_ptr - reader->buffer.ptr);
if (bom == GIT_BOM_UTF8)
reader->read_ptr += bom_offset;
/* TODO: reference implementation is pretty stupid with BoM */
return 0;
}
/*
(* basic types *)
digit = "0".."9"
integer = digit { digit }
alphabet = "a".."z" + "A" .. "Z"
section_char = alphabet | "." | "-"
extension_char = (* any character except newline *)
any_char = (* any character *)
variable_char = "alphabet" | "-"
(* actual grammar *)
config = { section }
section = header { definition }
header = "[" section [subsection | subsection_ext] "]"
subsection = "." section
subsection_ext = "\"" extension "\""
section = section_char { section_char }
extension = extension_char { extension_char }
definition = variable_name ["=" variable_value] "\n"
variable_name = variable_char { variable_char }
variable_value = string | boolean | integer
string = quoted_string | plain_string
quoted_string = "\"" plain_string "\""
plain_string = { any_char }
boolean = boolean_true | boolean_false
boolean_true = "yes" | "1" | "true" | "on"
boolean_false = "no" | "0" | "false" | "off"
*/
static int strip_comments(char *line, int in_quotes)
{
int quote_count = in_quotes, backslash_count = 0;
char *ptr;
for (ptr = line; *ptr; ++ptr) {
if (ptr[0] == '"' && ptr > line && ptr[-1] != '\\')
quote_count++;
if ((ptr[0] == ';' || ptr[0] == '#') &&
(quote_count % 2) == 0 &&
(backslash_count % 2) == 0) {
ptr[0] = '\0';
break;
}
if (ptr[0] == '\\')
backslash_count++;
else
backslash_count = 0;
}
/* skip any space at the end */
while (ptr > line && git__isspace(ptr[-1])) {
ptr--;
}
ptr[0] = '\0';
return quote_count;
}
static int included_path(git_buf *out, const char *dir, const char *path)
{
/* From the user's home */
if (path[0] == '~' && path[1] == '/')
return git_sysdir_expand_global_file(out, &path[1]);
return git_path_join_unrooted(out, path, dir, NULL);
}
static const char *escapes = "ntb\"\\";
static const char *escaped = "\n\t\b\"\\";
/* Escape the values to write them to the file */
static char *escape_value(const char *ptr)
{
git_buf buf;
size_t len;
const char *esc;
assert(ptr);
len = strlen(ptr);
if (!len)
return git__calloc(1, sizeof(char));
if (git_buf_init(&buf, len) < 0)
return NULL;
while (*ptr != '\0') {
if ((esc = strchr(escaped, *ptr)) != NULL) {
git_buf_putc(&buf, '\\');
git_buf_putc(&buf, escapes[esc - escaped]);
} else {
git_buf_putc(&buf, *ptr);
}
ptr++;
}
if (git_buf_oom(&buf)) {
git_buf_free(&buf);
return NULL;
}
return git_buf_detach(&buf);
}
/* '\"' -> '"' etc */
static int unescape_line(
char **out, bool *is_multi, const char *ptr, int quote_count)
{
char *str, *fixed, *esc;
size_t ptr_len = strlen(ptr), alloc_len;
*is_multi = false;
if (GIT_ADD_SIZET_OVERFLOW(&alloc_len, ptr_len, 1) ||
(str = git__malloc(alloc_len)) == NULL) {
return -1;
}
fixed = str;
while (*ptr != '\0') {
if (*ptr == '"') {
quote_count++;
} else if (*ptr != '\\') {
*fixed++ = *ptr;
} else {
/* backslash, check the next char */
ptr++;
/* if we're at the end, it's a multiline, so keep the backslash */
if (*ptr == '\0') {
*is_multi = true;
goto done;
}
if ((esc = strchr(escapes, *ptr)) != NULL) {
*fixed++ = escaped[esc - escapes];
} else {
git__free(str);
giterr_set(GITERR_CONFIG, "invalid escape at %s", ptr);
return -1;
}
}
ptr++;
}
done:
*fixed = '\0';
*out = str;
return 0;
}
static int parse_multiline_variable(struct reader *reader, git_buf *value, int in_quotes)
{
int quote_count;
bool multiline = true;
while (multiline) {
char *line = NULL, *proc_line = NULL;
int error;
/* Check that the next line exists */
line = reader_readline(reader, false);
GITERR_CHECK_ALLOC(line);
/*
* We've reached the end of the file, there is no continuation.
* (this is not an error).
*/
if (line[0] == '\0') {
error = 0;
goto out;
}
/* If it was just a comment, pretend it didn't exist */
quote_count = strip_comments(line, !!in_quotes);
if (line[0] == '\0')
goto next;
if ((error = unescape_line(&proc_line, &multiline,
line, in_quotes)) < 0)
goto out;
/* Add this line to the multiline var */
if ((error = git_buf_puts(value, proc_line)) < 0)
goto out;
next:
git__free(line);
git__free(proc_line);
in_quotes = quote_count;
continue;
out:
git__free(line);
git__free(proc_line);
return error;
}
return 0;
}
GIT_INLINE(bool) is_namechar(char c)
{
return isalnum(c) || c == '-';
}
static int parse_name(
char **name, const char **value, struct reader *reader, const char *line)
{
const char *name_end = line, *value_start;
*name = NULL;
*value = NULL;
while (*name_end && is_namechar(*name_end))
name_end++;
if (line == name_end) {
set_parse_error(reader, 0, "Invalid configuration key");
return -1;
}
value_start = name_end;
while (*value_start && git__isspace(*value_start))
value_start++;
if (*value_start == '=') {
*value = value_start + 1;
} else if (*value_start) {
set_parse_error(reader, 0, "Invalid configuration key");
return -1;
}
if ((*name = git__strndup(line, name_end - line)) == NULL)
return -1;
return 0;
}
static int parse_variable(struct reader *reader, char **var_name, char **var_value)
{
const char *value_start = NULL;
char *line;
int quote_count;
bool multiline;
line = reader_readline(reader, true);
if (line == NULL)
return -1;
quote_count = strip_comments(line, 0);
/* If there is no value, boolean true is assumed */
*var_value = NULL;
if (parse_name(var_name, &value_start, reader, line) < 0)
goto on_error;
/*
* Now, let's try to parse the value
*/
if (value_start != NULL) {
while (git__isspace(value_start[0]))
value_start++;
if (unescape_line(var_value, &multiline, value_start, 0) < 0)
goto on_error;
if (multiline) {
git_buf multi_value = GIT_BUF_INIT;
git_buf_attach(&multi_value, *var_value, 0);
if (parse_multiline_variable(reader, &multi_value, quote_count) < 0 ||
git_buf_oom(&multi_value)) {
git_buf_free(&multi_value);
goto on_error;
}
*var_value = git_buf_detach(&multi_value);
}
}
git__free(line);
return 0;
on_error:
git__free(*var_name);
git__free(line);
return -1;
}
static int config_parse(
struct reader *reader,
int (*on_section)(struct reader **reader, const char *current_section, const char *line, size_t line_len, void *data),
int (*on_variable)(struct reader **reader, const char *current_section, char *var_name, char *var_value, const char *line, size_t line_len, void *data),
int (*on_comment)(struct reader **reader, const char *line, size_t line_len, void *data),
int (*on_eof)(struct reader **reader, const char *current_section, void *data),
void *data)
{
char *current_section = NULL, *var_name, *var_value, *line_start;
char c;
size_t line_len;
int result = 0;
skip_bom(reader);
while (result == 0 && !reader->eof) {
line_start = reader->read_ptr;
c = reader_peek(reader, SKIP_WHITESPACE);
switch (c) {
case '\0': /* EOF when peeking, set EOF in the reader to exit the loop */
reader->eof = 1;
break;
case '[': /* section header, new section begins */
git__free(current_section);
current_section = NULL;
if ((result = parse_section_header(reader, ¤t_section)) == 0 && on_section) {
line_len = reader->read_ptr - line_start;
result = on_section(&reader, current_section, line_start, line_len, data);
}
break;
case '\n': /* comment or whitespace-only */
case ';':
case '#':
reader_consume_line(reader);
if (on_comment) {
line_len = reader->read_ptr - line_start;
result = on_comment(&reader, line_start, line_len, data);
}
break;
default: /* assume variable declaration */
if ((result = parse_variable(reader, &var_name, &var_value)) == 0 && on_variable) {
line_len = reader->read_ptr - line_start;
result = on_variable(&reader, current_section, var_name, var_value, line_start, line_len, data);
}
break;
}
}
if (on_eof)
result = on_eof(&reader, current_section, data);
git__free(current_section);
return result;
}
struct parse_data {
git_strmap *values;
diskfile_backend *cfg_file;
uint32_t reader_idx;
git_config_level_t level;
int depth;
};
static int read_on_variable(
struct reader **reader,
const char *current_section,
char *var_name,
char *var_value,
const char *line,
size_t line_len,
void *data)
{
struct parse_data *parse_data = (struct parse_data *)data;
git_buf buf = GIT_BUF_INIT;
cvar_t *var;
int result = 0;
GIT_UNUSED(line);
GIT_UNUSED(line_len);
git__strtolower(var_name);
git_buf_printf(&buf, "%s.%s", current_section, var_name);
git__free(var_name);
if (git_buf_oom(&buf)) {
git__free(var_value);
return -1;
}
var = git__calloc(1, sizeof(cvar_t));
GITERR_CHECK_ALLOC(var);
var->entry = git__calloc(1, sizeof(git_config_entry));
GITERR_CHECK_ALLOC(var->entry);
var->entry->name = git_buf_detach(&buf);
var->entry->value = var_value;
var->entry->level = parse_data->level;
var->included = !!parse_data->depth;
if ((result = append_entry(parse_data->values, var)) < 0)
return result;
result = 0;
/* Add or append the new config option */
if (!git__strcmp(var->entry->name, "include.path") && var->entry->value) {
struct reader *r;
git_buf path = GIT_BUF_INIT;
char *dir;
uint32_t index;
r = git_array_alloc(parse_data->cfg_file->readers);
/* The reader may have been reallocated */
*reader = git_array_get(parse_data->cfg_file->readers, parse_data->reader_idx);
memset(r, 0, sizeof(struct reader));
if ((result = git_path_dirname_r(&path, (*reader)->file_path)) < 0)
return result;
/* We need to know our index in the array, as the next config_parse call may realloc */
index = git_array_size(parse_data->cfg_file->readers) - 1;
dir = git_buf_detach(&path);
result = included_path(&path, dir, var->entry->value);
git__free(dir);
if (result < 0)
return result;
r->file_path = git_buf_detach(&path);
git_buf_init(&r->buffer, 0);
result = git_futils_readbuffer_updated(
&r->buffer, r->file_path, &r->checksum, NULL);
if (result == 0) {
result = config_read(parse_data->values, parse_data->cfg_file, r, parse_data->level, parse_data->depth+1);
r = git_array_get(parse_data->cfg_file->readers, index);
*reader = git_array_get(parse_data->cfg_file->readers, parse_data->reader_idx);
} else if (result == GIT_ENOTFOUND) {
giterr_clear();
result = 0;
}
git_buf_free(&r->buffer);
}
return result;
}
static int config_read(git_strmap *values, diskfile_backend *cfg_file, struct reader *reader, git_config_level_t level, int depth)
{
struct parse_data parse_data;
if (depth >= MAX_INCLUDE_DEPTH) {
giterr_set(GITERR_CONFIG, "maximum config include depth reached");
return -1;
}
/* Initialize the reading position */
reader->read_ptr = reader->buffer.ptr;
reader->eof = 0;
/* If the file is empty, there's nothing for us to do */
if (*reader->read_ptr == '\0')
return 0;
parse_data.values = values;
parse_data.cfg_file = cfg_file;
parse_data.reader_idx = git_array_size(cfg_file->readers) - 1;
parse_data.level = level;
parse_data.depth = depth;
return config_parse(reader, NULL, read_on_variable, NULL, NULL, &parse_data);
}
static int write_section(git_buf *fbuf, const char *key)
{
int result;
const char *dot;
git_buf buf = GIT_BUF_INIT;
/* All of this just for [section "subsection"] */
dot = strchr(key, '.');
git_buf_putc(&buf, '[');
if (dot == NULL) {
git_buf_puts(&buf, key);
} else {
char *escaped;
git_buf_put(&buf, key, dot - key);
escaped = escape_value(dot + 1);
GITERR_CHECK_ALLOC(escaped);
git_buf_printf(&buf, " \"%s\"", escaped);
git__free(escaped);
}
git_buf_puts(&buf, "]\n");
if (git_buf_oom(&buf))
return -1;
result = git_buf_put(fbuf, git_buf_cstr(&buf), buf.size);
git_buf_free(&buf);
return result;
}
static const char *quotes_for_value(const char *value)
{
const char *ptr;
if (value[0] == ' ' || value[0] == '\0')
return "\"";
for (ptr = value; *ptr; ++ptr) {
if (*ptr == ';' || *ptr == '#')
return "\"";
}
if (ptr[-1] == ' ')
return "\"";
return "";
}
struct write_data {
git_buf *buf;
git_buf buffered_comment;
unsigned int in_section : 1,
preg_replaced : 1;
const char *section;
const char *name;
const regex_t *preg;
const char *value;
};
static int write_line_to(git_buf *buf, const char *line, size_t line_len)
{
int result = git_buf_put(buf, line, line_len);
if (!result && line_len && line[line_len-1] != '\n')
result = git_buf_printf(buf, "\n");
return result;
}
static int write_line(struct write_data *write_data, const char *line, size_t line_len)
{
return write_line_to(write_data->buf, line, line_len);
}
static int write_value(struct write_data *write_data)
{
const char *q;
int result;
q = quotes_for_value(write_data->value);
result = git_buf_printf(write_data->buf,
"\t%s = %s%s%s\n", write_data->name, q, write_data->value, q);
/* If we are updating a single name/value, we're done. Setting `value`
* to `NULL` will prevent us from trying to write it again later (in
* `write_on_section`) if we see the same section repeated.
*/
if (!write_data->preg)
write_data->value = NULL;
return result;
}
static int write_on_section(
struct reader **reader,
const char *current_section,
const char *line,
size_t line_len,
void *data)
{
struct write_data *write_data = (struct write_data *)data;
int result = 0;
GIT_UNUSED(reader);
/* If we were previously in the correct section (but aren't anymore)
* and haven't written our value (for a simple name/value set, not
* a multivar), then append it to the end of the section before writing
* the new one.
*/
if (write_data->in_section && !write_data->preg && write_data->value)
result = write_value(write_data);
write_data->in_section = strcmp(current_section, write_data->section) == 0;
/*
* If there were comments just before this section, dump them as well.
*/
if (!result) {
result = git_buf_put(write_data->buf, write_data->buffered_comment.ptr, write_data->buffered_comment.size);
git_buf_clear(&write_data->buffered_comment);
}
if (!result)
result = write_line(write_data, line, line_len);
return result;
}
static int write_on_variable(
struct reader **reader,
const char *current_section,
char *var_name,
char *var_value,
const char *line,
size_t line_len,
void *data)
{
struct write_data *write_data = (struct write_data *)data;
bool has_matched = false;
int error;
GIT_UNUSED(reader);
GIT_UNUSED(current_section);
/*
* If there were comments just before this variable, let's dump them as well.
*/
if ((error = git_buf_put(write_data->buf, write_data->buffered_comment.ptr, write_data->buffered_comment.size)) < 0)
return error;
git_buf_clear(&write_data->buffered_comment);
/* See if we are to update this name/value pair; first examine name */
if (write_data->in_section &&
strcasecmp(write_data->name, var_name) == 0)
has_matched = true;
/* If we have a regex to match the value, see if it matches */
if (has_matched && write_data->preg != NULL)
has_matched = (regexec(write_data->preg, var_value, 0, NULL, 0) == 0);
git__free(var_name);
git__free(var_value);
/* If this isn't the name/value we're looking for, simply dump the
* existing data back out and continue on.
*/
if (!has_matched)
return write_line(write_data, line, line_len);
write_data->preg_replaced = 1;
/* If value is NULL, we are deleting this value; write nothing. */
if (!write_data->value)
return 0;
return write_value(write_data);
}
static int write_on_comment(struct reader **reader, const char *line, size_t line_len, void *data)
{
struct write_data *write_data;
GIT_UNUSED(reader);
write_data = (struct write_data *)data;
return write_line_to(&write_data->buffered_comment, line, line_len);
}
static int write_on_eof(
struct reader **reader, const char *current_section, void *data)
{
struct write_data *write_data = (struct write_data *)data;
int result = 0;
GIT_UNUSED(reader);
/*
* If we've buffered comments when reaching EOF, make sure to dump them.
*/
if ((result = git_buf_put(write_data->buf, write_data->buffered_comment.ptr, write_data->buffered_comment.size)) < 0)
return result;
/* If we are at the EOF and have not written our value (again, for a
* simple name/value set, not a multivar) then we have never seen the
* section in question and should create a new section and write the
* value.
*/
if ((!write_data->preg || !write_data->preg_replaced) && write_data->value) {
/* write the section header unless we're already in it */
if (!current_section || strcmp(current_section, write_data->section))
result = write_section(write_data->buf, write_data->section);
if (!result)
result = write_value(write_data);
}
return result;
}
/*
* This is pretty much the parsing, except we write out anything we don't have
*/
static int config_write(diskfile_backend *cfg, const char *key, const regex_t *preg, const char* value)
{
int result;
char *section, *name, *ldot;
git_filebuf file = GIT_FILEBUF_INIT;
git_buf buf = GIT_BUF_INIT;
struct reader *reader = git_array_get(cfg->readers, 0);
struct write_data write_data;
if (cfg->locked) {
result = git_buf_puts(&reader->buffer, git_buf_cstr(&cfg->locked_content));
} else {
/* Lock the file */
if ((result = git_filebuf_open(
&file, cfg->file_path, GIT_FILEBUF_HASH_CONTENTS, GIT_CONFIG_FILE_MODE)) < 0) {
git_buf_free(&reader->buffer);
return result;
}
/* We need to read in our own config file */
result = git_futils_readbuffer(&reader->buffer, cfg->file_path);
}
/* Initialise the reading position */
if (result == GIT_ENOTFOUND) {
reader->read_ptr = NULL;
reader->eof = 1;
git_buf_clear(&reader->buffer);
} else if (result == 0) {
reader->read_ptr = reader->buffer.ptr;
reader->eof = 0;
} else {
git_filebuf_cleanup(&file);
return -1; /* OS error when reading the file */
}
ldot = strrchr(key, '.');
name = ldot + 1;
section = git__strndup(key, ldot - key);
write_data.buf = &buf;
git_buf_init(&write_data.buffered_comment, 0);
write_data.section = section;
write_data.in_section = 0;
write_data.preg_replaced = 0;
write_data.name = name;
write_data.preg = preg;
write_data.value = value;
result = config_parse(reader, write_on_section, write_on_variable, write_on_comment, write_on_eof, &write_data);
git__free(section);
git_buf_free(&write_data.buffered_comment);
if (result < 0) {
git_filebuf_cleanup(&file);
goto done;
}
if (cfg->locked) {
size_t len = buf.asize;
/* Update our copy with the modified contents */
git_buf_free(&cfg->locked_content);
git_buf_attach(&cfg->locked_content, git_buf_detach(&buf), len);
} else {
git_filebuf_write(&file, git_buf_cstr(&buf), git_buf_len(&buf));
result = git_filebuf_commit(&file);
}
done:
git_buf_free(&buf);
git_buf_free(&reader->buffer);
return result;
}