platform: extract git remote url's from config with regex

issue #2

src/platform/base.c

@@ -3,7 +3,9 @@
 #include "../tools/log.h"
 
 #include <stdio.h>
+#include <stdbool.h>
 #include <string.h>
+#include <regex.h>
 #include <errno.h>
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -14,6 +16,97 @@ const char* SUPPORTED_PLATFORM_NAMES [] = {
     "gitlab.com"
 };
 
+static void throw_regex_error(int errcode, const regex_t *preg, const char* str) {
+    char regex_error_buffer[REGEX_ERROR_STR_MAX_LEN] = {0};
+    size_t written = regerror(errcode, preg, regex_error_buffer, REGEX_ERROR_STR_MAX_LEN);
+    LOG_DEBUG("regex_error_str() errcode: %d, regerror ret: %lu", errcode, written);
+    LOG_ERROR_EXIT("Regex compilation error for str: %s (%s)", str, regex_error_buffer);
+}
+
+static bool parse_regex_result(int value) {
+    if (value == 0) {
+        return true;
+    } else if (value == REG_NOMATCH) {
+        return false;
+    } else {
+        LOG_ERROR_EXIT("Regex matching failed");
+    }
+}
+
+static Lines* get_git_remote_urls_from_lines(Lines* lines, const char* remote) {
+    LOG_DEBUG("Entering function %s", __func__);
+    char config_remote_line_rg [GIT_CONFIG_REMOTE_STRING_MAX_LEN] = {0};
+    const int config_remote_line_written_bytes = snprintf(
+        config_remote_line_rg,
+        GIT_CONFIG_REMOTE_STRING_MAX_LEN,
+        "\\[remote \"%s\"]",
+        remote);
+    if (config_remote_line_written_bytes < 0) {
+        LOG_ERROR_EXIT("Failed generating remote string [remote \"value\"]. Value %s",
+        remote);
+    }
+    RegexWrapper regexes [GIT_CFG_RG_COUNT] = {
+        {.regex_pattern = config_remote_line_rg},
+        {.regex_pattern = GIT_CONFIG_NEXT_SECTION_RG},
+        {.regex_pattern = GIT_CONFIG_REMOTE_URL_RG}
+    };
+    for (size_t i = 0; i < GIT_CFG_RG_COUNT; i++) {
+        int value = regcomp(&(regexes[i].regex_holder), regexes[i].regex_pattern, 0);
+        if (value != 0) throw_regex_error(value, &(regexes[i].regex_holder), regexes[i].regex_pattern);
+    }
+
+    bool remote_section_found = false;
+    bool inside_remote_section = false;
+    Lines* git_remote_urls = lines_create(1);
+    Buffer* remote_url_buffer = buffer_create(1);
+    for (size_t i = 0; i < lines->size; i++) {
+        if (remote_section_found) { 
+            bool next_section_met = (parse_regex_result(regexec(
+                &(regexes[GIT_CFG_RG_NEXT_SECTION].regex_holder),
+                lines->lines[i]->data,
+                0, NULL, 0)));
+            if (!next_section_met) {
+                inside_remote_section = true;
+                LOG_DEBUG("inside_remote_section = true");
+            } else {
+                inside_remote_section = false;
+                remote_section_found = false;
+                LOG_DEBUG("inside_remote_section = false");
+                LOG_DEBUG("remote_section_found = false");
+            }
+        }
+        if (inside_remote_section) {
+            bool url_found = (parse_regex_result(regexec(
+                &(regexes[GIT_CFG_RG_REMOTE_URL].regex_holder),
+                lines->lines[i]->data,
+                0, NULL, 0)));
+            if (url_found) {
+                LOG_DEBUG("url_found: %s", lines->lines[i]->data);
+                buffer_append(remote_url_buffer, lines->lines[i]->data);
+                lines_append(git_remote_urls, remote_url_buffer);
+                remote_url_buffer->size = 0;
+                continue;
+            }
+            LOG_DEBUG("url not found inside remote. Line: %s", lines->lines[i]->data);
+        }
+        if (parse_regex_result(regexec(
+                &(regexes[GIT_CFG_RG_USER_GIVEN_REMOTE].regex_holder),
+                lines->lines[i]->data,
+                0, NULL, 0))
+            ) {
+                remote_section_found = true;
+                LOG_DEBUG("remote_section_found = true");
+                continue;
+        }
+    }
+    for (size_t i = 0; i < GIT_CFG_RG_COUNT; i++) {
+        regfree(&(regexes[i].regex_holder));
+    }
+    buffer_free(remote_url_buffer);
+
+    return git_remote_urls;
+}
+
 PlaformId identify_platfrom_from_project(const char* project_path, const char* remote) {
     LOG_DEBUG("Entering function %s", __func__);
     if (project_path == NULL) {
@@ -26,8 +119,10 @@ PlaformId identify_platfrom_from_project(const char* project_path, const char* r
 
     Lines* config_file_lines = read_file_lines(git_config_path_buffer->data);
     //TODO: from remote "origin" get url
+    Lines* git_remote_urls = get_git_remote_urls_from_lines(config_file_lines, remote);
     //TODO: parse remote "origin url" to get platform
-    lines_flush(config_file_lines);
+    lines_free(config_file_lines);
+    lines_flush(git_remote_urls);
     buffer_free(git_config_path_buffer);
     return PL_UNRECOGNIZED;
 }

src/platform/base.h

@@ -1,7 +1,13 @@
 #ifndef __PLATFORM_BASE_H__
 #define __PLATFORM_BASE_H__
 
+#include <regex.h>
+
 #define PATH_TO_GIT_CONFIG_RELATIVE_TO_PROJ "/.git/config"
+#define REGEX_ERROR_STR_MAX_LEN 512
+#define GIT_CONFIG_REMOTE_STRING_MAX_LEN 256
+#define GIT_CONFIG_NEXT_SECTION_RG "\\[.*"
+#define GIT_CONFIG_REMOTE_URL_RG ".*url.*"
 
 typedef enum PlaformId {
     PL_GITHUB,
@@ -9,6 +15,18 @@ typedef enum PlaformId {
     PL_UNRECOGNIZED
 } PlaformId;
 
+typedef enum GitConfigRegexes {
+    GIT_CFG_RG_USER_GIVEN_REMOTE,
+    GIT_CFG_RG_NEXT_SECTION,
+    GIT_CFG_RG_REMOTE_URL,
+    GIT_CFG_RG_COUNT
+} GitConfigRegexes;
+
+typedef struct RegexWrapper {
+    const char* regex_pattern;
+    regex_t regex_holder;
+} RegexWrapper;
+
 extern const char* SUPPORTED_PLATFORM_NAMES [];
 
 PlaformId identify_platfrom_from_project(const char* project_path, const char* remote);

src/tools/buffer.h

@@ -3,6 +3,8 @@
 
 #include <stdlib.h>
 
+#define ARRAY_SIZE(arr) (sizeof((arr)) / sizeof((arr)[0]))
+
 typedef struct {
     char* data;
     size_t size;