From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tanay Abhra Subject: [PATCH v1] config: Add hashtable for config parsing & retrival Date: Mon, 9 Jun 2014 05:49:06 -0700 Message-ID: <1402318146-5062-2-git-send-email-tanayabh@gmail.com> References: <1402318146-5062-1-git-send-email-tanayabh@gmail.com> Cc: Tanay Abhra , Ramkumar Ramachandra , Matthieu Moy , Eric Sunshine , Jeff King , Torsten Bogershausen To: git@vger.kernel.org X-From: git-owner@vger.kernel.org Mon Jun 09 14:52:01 2014 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Wtz3M-0000z4-T4 for gcvg-git-2@plane.gmane.org; Mon, 09 Jun 2014 14:51:57 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755130AbaFIMvy (ORCPT ); Mon, 9 Jun 2014 08:51:54 -0400 Received: from mail-pa0-f50.google.com ([209.85.220.50]:54243 "EHLO mail-pa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755026AbaFIMvs (ORCPT ); Mon, 9 Jun 2014 08:51:48 -0400 Received: by mail-pa0-f50.google.com with SMTP id fb1so717495pad.37 for ; Mon, 09 Jun 2014 05:51:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=RV+vaydIlpFUQQPqQc4y5tDukGZ1flZzeUL9A8/pwN4=; b=NGPghp65J1LipGjqh3qJx7qsrBB9ZhVhsObySdGaBqVs/bVUVzBdCeCP1bag4jsPAO ILjCzatbvKtTQ9/M86+xv7CLlKVOTNWeLip8D9E26PuHtij49YuADAsADJCOlY8mqN0N lZ1/cyGrX3E89TWzMD2HZKUY1/cH1G9e+5WdZr1mtCDFfCHZXlX0YpdjfEVgiH3irBIa hI1awieqDSq45zpKyokdevVZ+olTUgYhaNEE+khCxraw0d9J/hYW/uUSB79MqRsDshvM VQVxjS8qoH4slbD8HSevgL4CoslNRpFSc+7bnLZUwL03UVeYbhvnVd4ok38jy/ruLWAJ WOmg== X-Received: by 10.66.148.230 with SMTP id tv6mr3309623pab.155.1402318308396; Mon, 09 Jun 2014 05:51:48 -0700 (PDT) Received: from localhost.localdomain ([117.254.220.136]) by mx.google.com with ESMTPSA id qw8sm63962212pbb.27.2014.06.09.05.51.43 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 09 Jun 2014 05:51:47 -0700 (PDT) X-Mailer: git-send-email 1.9.0.GIT In-Reply-To: <1402318146-5062-1-git-send-email-tanayabh@gmail.com> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Add a hash table to cache all key-value pairs read from config files (repo specific .git/config, user wide ~/.gitconfig and the global /etc/gitconfig). Add two external functions `git_config_get_string` and `git_config_get_string_multi` for querying in a non-callback manner from the hash table. Signed-off-by: Tanay Abhra --- Documentation/technical/api-config.txt | 18 +++++ cache.h | 2 + config.c | 122 +++++++++++++++++++++++++++++++++ 3 files changed, 142 insertions(+) diff --git a/Documentation/technical/api-config.txt b/Documentation/technical/api-config.txt index 230b3a0..5b6e376 100644 --- a/Documentation/technical/api-config.txt +++ b/Documentation/technical/api-config.txt @@ -77,6 +77,24 @@ To read a specific file in git-config format, use `git_config_from_file`. This takes the same callback and data parameters as `git_config`. +Querying For Specific Variables +------------------------------- + +For programs wanting to query for specific variables in a non-callback +manner, the config API provides two functions `git_config_get_string` +and `git_config_get_string_multi`. They both take a single parameter, + +- a key string in canonical flat form for which the corresponding values + will be retrieved and returned. + +They both read values from an internal cache generated previously from +reading the config files. `git_config_get_string` returns the value with +the highest priority(i.e. for the same variable value in the repo config +will be preferred over value in user wide config). + +`git_config_get_string_multi` returns a `string_list` containing all the +values for that particular key, sorted in order of increasing priority. + Value Parsing Helpers --------------------- diff --git a/cache.h b/cache.h index 107ac61..2038150 100644 --- a/cache.h +++ b/cache.h @@ -1271,6 +1271,8 @@ extern int check_repository_format_version(const char *var, const char *value, v extern int git_env_bool(const char *, int); extern int git_config_system(void); extern int config_error_nonbool(const char *); +extern const char *git_config_get_string(const char *); +extern const struct string_list *git_config_get_string_multi(const char *); #if defined(__GNUC__) && ! defined(__clang__) #define config_error_nonbool(s) (config_error_nonbool(s), -1) #endif diff --git a/config.c b/config.c index a30cb5c..6f6b04e 100644 --- a/config.c +++ b/config.c @@ -9,6 +9,8 @@ #include "exec_cmd.h" #include "strbuf.h" #include "quote.h" +#include "hashmap.h" +#include "string-list.h" struct config_source { struct config_source *prev; @@ -37,6 +39,120 @@ static struct config_source *cf; static int zlib_compression_seen; +struct config_cache_entry { + struct hashmap_entry ent; + char *key; + struct string_list *value_list; +}; + +static int hashmap_is_init; + +static int config_cache_set_value(const char *key, const char *value); + +static int config_cache_entry_cmp_case(const struct config_cache_entry *e1, + const struct config_cache_entry *e2, const void *unused) +{ + return strcmp(e1->key, e2->key); +} + +static void config_cache_init(struct hashmap *config_cache) +{ + hashmap_init(config_cache, (hashmap_cmp_fn) config_cache_entry_cmp_case, 0); +} + +static int config_cache_callback(const char *key, const char *value, void *unused) +{ + config_cache_set_value(key, value); + return 0; +} + +static struct hashmap *get_config_cache(void) +{ + static struct hashmap config_cache; + if (!hashmap_is_init) { + config_cache_init(&config_cache); + hashmap_is_init = 1; + git_config(config_cache_callback, NULL); + return &config_cache; + } + return &config_cache; +} + +static void config_cache_free(void) +{ + struct hashmap *config_cache; + struct config_cache_entry *entry; + struct hashmap_iter iter; + config_cache = get_config_cache(); + hashmap_iter_init(config_cache, &iter); + while ((entry = hashmap_iter_next(&iter))) { + free(entry->key); + string_list_clear(entry->value_list, 0); + } + hashmap_free(config_cache, 1); + hashmap_is_init = 0; +} + +static struct config_cache_entry *config_cache_find_entry(const char *key) +{ + struct hashmap *config_cache; + struct config_cache_entry k; + char *normalized_key; + int baselength = 0, ret; + config_cache = get_config_cache(); + ret = git_config_parse_key(key, &normalized_key, &baselength); + + if (ret) + return NULL; + + hashmap_entry_init(&k, strhash(normalized_key)); + k.key = (char*) key; + return hashmap_get(config_cache, &k, NULL); +} + +static struct string_list *config_cache_get_value(const char *key) +{ + struct config_cache_entry *e = config_cache_find_entry(key); + return e ? e->value_list : NULL; +} + + +static int config_cache_set_value(const char *key, const char *value) +{ + struct hashmap *config_cache; + struct config_cache_entry *e; + + config_cache = get_config_cache(); + e = config_cache_find_entry(key); + if (!e) { + e = xmalloc(sizeof(*e)); + hashmap_entry_init(e, strhash(key)); + e->key = xstrdup(key); + e->value_list = xcalloc(sizeof(struct string_list), 1); + e->value_list->strdup_strings = 1; + string_list_append(e->value_list, value); + hashmap_add(config_cache, e); + } else { + string_list_append(e->value_list, value); + } + return 0; +} + +extern const char *git_config_get_string(const char *key) +{ + struct string_list *values; + values = config_cache_get_value(key); + if (!values) + return NULL; + assert(values->nr > 0); + return values->items[values->nr - 1].string; +} + +extern const struct string_list *git_config_get_string_multi(const char *key) +{ + return config_cache_get_value(key); +} + static int config_file_fgetc(struct config_source *conf) { return fgetc(conf->u.file); @@ -1700,6 +1816,12 @@ int git_config_set_multivar_in_file(const char *config_filename, lock = NULL; ret = 0; + /* contents of config file has changed, so invalidate the + * config cache used by non-callback based query functions. + */ + if (hashmap_is_init) + config_cache_free(); + out_free: if (lock) rollback_lock_file(lock); -- 1.9.0.GIT