path: root/src/pacman/ini.c

/*
 *  ini.c
 *
 *  Copyright (c) 2013-2014 Pacman Development Team <pacman-dev@archlinux.org>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <errno.h>
#include <glob.h>
#include <limits.h>
#include <string.h> /* strdup */

#include <alpm.h>

#include "ini.h"
#include "util.h"

static const int ini_max_recursion = 10;

/**
 * @brief INI parser backend.
 *
 * @param file path to the config file
 * @param cb callback for key/value pairs
 * @param data caller defined data to be passed to the callback
 * @param section_name the name of the current section
 * @param line buffer to read into, must be at least PATH_MAX long
 * @param depth recursion depth, should initially be 0
 *
 * @return 0 on success, 1 on parsing errors, the callback return value
 * otherwise
 */
static int _parse_ini(const char *file, ini_parser_fn cb, void *data,
                char **section_name, char *line, int depth)
{
        FILE *fp = NULL;
        int linenum = 0;
        int ret = 0;

        if(depth >= ini_max_recursion) {
                pm_printf(ALPM_LOG_ERROR,
                                _("config parsing exceeded max recursion depth of %d.\n"),
                                ini_max_recursion);
                ret = 1;
                goto cleanup;
        }

        pm_printf(ALPM_LOG_DEBUG, "config: attempting to read file %s\n", file);
        fp = fopen(file, "r");
        if(fp == NULL) {
                pm_printf(ALPM_LOG_ERROR, _("config file %s could not be read: %s\n"),
                                file, strerror(errno));
                ret = 1;
                goto cleanup;
        }

        while(fgets(line, PATH_MAX, fp)) {
                char *key, *value, *ptr;
                size_t line_len;

                linenum++;

                /* ignore whole line and end of line comments */
                if((ptr = strchr(line, '#'))) {
                        *ptr = '\0';
                }

                line_len = strtrim(line);

                if(line_len == 0) {
                        continue;
                }

                if(line[0] == '[' && line[line_len - 1] == ']') {
                        char *name;
                        /* only possibility here is a line == '[]' */
                        if(line_len <= 2) {
                                pm_printf(ALPM_LOG_ERROR, _("config file %s, line %d: bad section name.\n"),
                                                file, linenum);
                                ret = 1;
                                goto cleanup;
                        }
                        /* new config section, skip the '[' */
                        name = strdup(line + 1);
                        name[line_len - 2] = '\0';

                        ret = cb(file, linenum, name, NULL, NULL, data);
                        free(*section_name);
                        *section_name = name;

                        /* we're at a new section; perform any post-actions for the prior */
                        if(ret) {
                                goto cleanup;
                        }
                        continue;
                }

                /* directive */
                /* strsep modifies the 'line' string: 'key \0 value' */
                key = line;
                value = line;
                strsep(&value, "=");
                strtrim(key);
                strtrim(value);

                if(key == NULL) {
                        pm_printf(ALPM_LOG_ERROR, _("config file %s, line %d: syntax error in config file- missing key.\n"),
                                        file, linenum);
                        ret = 1;
                        goto cleanup;
                }
                /* Include is allowed in both options and repo sections */
                if(strcmp(key, "Include") == 0) {
                        glob_t globbuf;
                        int globret;
                        size_t gindex;

                        if(value == NULL) {
                                pm_printf(ALPM_LOG_ERROR, _("config file %s, line %d: directive '%s' needs a value\n"),
                                                file, linenum, key);
                                ret = 1;
                                goto cleanup;
                        }
                        /* Ignore include failures... assume non-critical */
                        globret = glob(value, GLOB_NOCHECK, NULL, &globbuf);
                        switch(globret) {
                                case GLOB_NOSPACE:
                                        pm_printf(ALPM_LOG_DEBUG,
                                                        "config file %s, line %d: include globbing out of space\n",
                                                        file, linenum);
                                        break;
                                case GLOB_ABORTED:
                                        pm_printf(ALPM_LOG_DEBUG,
                                                        "config file %s, line %d: include globbing read error for %s\n",
                                                        file, linenum, value);
                                        break;
                                case GLOB_NOMATCH:
                                        pm_printf(ALPM_LOG_DEBUG,
                                                        "config file %s, line %d: no include found for %s\n",
                                                        file, linenum, value);
                                        break;
                                default:
                                        for(gindex = 0; gindex < globbuf.gl_pathc; gindex++) {
                                                pm_printf(ALPM_LOG_DEBUG, "config file %s, line %d: including %s\n",
                                                                file, linenum, globbuf.gl_pathv[gindex]);
                                                ret =_parse_ini(globbuf.gl_pathv[gindex], cb, data,
                                                                section_name, line, depth + 1);
                                                if(ret) {
                                                        globfree(&globbuf);
                                                        goto cleanup;
                                                }
                                        }
                                        break;
                        }
                        globfree(&globbuf);
                        continue;
                }
                if((ret = cb(file, linenum, *section_name, key, value, data)) != 0) {
                        goto cleanup;
                }
        }

        if(depth == 0) {
                ret = cb(NULL, 0, NULL, NULL, NULL, data);
        }

cleanup:
        if(fp) {
                fclose(fp);
        }
        if(depth == 0) {
                free(*section_name);
                *section_name = NULL;
        }
        pm_printf(ALPM_LOG_DEBUG, "config: finished parsing %s\n", file);
        return ret;
}

/**
 * @brief Parse a pacman-style INI config file.
 *
 * @param file path to the config file
 * @param cb callback for key/value pairs
 * @param data caller defined data to be passed to the callback
 *
 * @return 0 on success, 1 on parsing errors, the callback return value
 * otherwise
 *
 * @note The callback will be called at the beginning of each section with an
 * empty key and value, for each key/value pair, and when parsing is complete
 * with all arguments except @a data empty.
 *
 * @note The @a key and @a value passed to @ cb will be overwritten between
 * calls.  The section name will remain valid until after @a cb is called to
 * begin a new section.
 *
 * @note Parsing will immediately stop if the callback returns non-zero.
 */
int parse_ini(const char *file, ini_parser_fn cb, void *data)
{
        char *section_name = NULL, line[PATH_MAX];
        return _parse_ini(file, cb, data, &section_name, line, 0);
}

/* vim: set noet: */