git-receiver: splitted code

1 files changed, 206 insertions, 0 deletions

diff --git a/src/blogc-git-receiver/shell.c b/src/blogc-git-receiver/shell.c
new file mode 100644
index 0000000..290526b
--- /dev/null
+++ b/src/blogc-git-receiver/shell.c
@@ -0,0 +1,206 @@
+/*
+ * blogc: A blog compiler.
+ * Copyright (C) 2015-2016 Rafael G. Martins <rafael@rafaelmartins.eng.br>
+ *
+ * This program can be distributed under the terms of the BSD License.
+ * See the file LICENSE.
+ */
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include "../common/utils.h"
+#include "shell.h"
+
+#ifndef BUFFER_SIZE
+#define BUFFER_SIZE 4096
+#endif
+
+
+int
+bgr_shell(int argc, char *argv[])
+{
+    int rv = 0;
+
+    char *repo = NULL;
+    char *command_orig = NULL;
+    char *command_name = NULL;
+    char command_new[BUFFER_SIZE];
+
+    bool exec_git = false;
+
+    // validate git command
+    size_t len = strlen(argv[2]);
+    if (!((len > 17 && (0 == strncmp(argv[2], "git-receive-pack ", 17))) ||
+          (len > 16 && (0 == strncmp(argv[2], "git-upload-pack ", 16))) ||
+          (len > 19 && (0 == strncmp(argv[2], "git-upload-archive ", 19)))))
+    {
+        fprintf(stderr, "error: unsupported git command: %s\n", argv[2]);
+        rv = 1;
+        goto cleanup;
+    }
+
+    // get shell path
+    char *self = getenv("SHELL");
+    if (self == NULL) {
+        fprintf(stderr, "error: failed to find blogc-git-receiver path\n");
+        rv = 1;
+        goto cleanup;
+    }
+
+    // get home path
+    char *home = getenv("HOME");
+    if (home == NULL) {
+        fprintf(stderr, "error: failed to find user home path\n");
+        rv = 1;
+        goto cleanup;
+    }
+
+    // get git repository
+    command_orig = bc_strdup(argv[2]);
+    char *p, *r;
+    for (p = command_orig; *p != ' ' && *p != '\0'; p++);
+    if (*p == ' ')
+        p++;
+    if (*p == '\'' || *p == '"')
+        p++;
+    if (*p == '/')
+        p++;
+    for (r = p; *p != '\'' && *p != '"' && *p != '\0'; p++);
+    if (*p == '\'' || *p == '"')
+        *p = '\0';
+    if (*--p == '/')
+        *p = '\0';
+
+    repo = bc_strdup_printf("repos/%s", r);
+
+    // check if repository is sane
+    if (0 == strlen(repo)) {
+        fprintf(stderr, "error: invalid repository\n");
+        rv = 1;
+        goto cleanup;
+    }
+
+    if (0 == strncmp(argv[2], "git-upload-", 11))  // no need to check len here
+        goto git_exec;
+
+    if (0 != chdir(home)) {
+        fprintf(stderr, "error: failed to chdir (%s): %s\n", home,
+            strerror(errno));
+        rv = 1;
+        goto cleanup;
+    }
+
+    if (0 != access(repo, F_OK)) {
+        char *git_init_cmd = bc_strdup_printf(
+            "git init --bare \"%s\" > /dev/null", repo);
+        if (0 != system(git_init_cmd)) {
+            fprintf(stderr, "error: failed to create git repository: %s\n",
+                repo);
+            rv = 1;
+            free(git_init_cmd);
+            goto cleanup;
+        }
+        free(git_init_cmd);
+    }
+
+    if (0 != chdir(repo)) {
+        fprintf(stderr, "error: failed to chdir (%s/%s): %s\n", home, repo,
+            strerror(errno));
+        rv = 1;
+        goto cleanup;
+    }
+
+    if (0 != access("hooks", F_OK)) {
+        // openwrt git package won't install git templates, then the git
+        // repositories created with it won't have the hooks/ directory.
+        if (0 != mkdir("hooks", 0777)) {  // mkdir honors umask for us.
+            fprintf(stderr, "error: failed to create directory (%s/%s/hooks): "
+                "%s\n", home, repo, strerror(errno));
+            rv = 1;
+            goto cleanup;
+        }
+    }
+
+    if (0 != chdir("hooks")) {
+        fprintf(stderr, "error: failed to chdir (%s/%s/hooks): %s\n", home,
+            repo, strerror(errno));
+        rv = 1;
+        goto cleanup;
+    }
+
+    if (0 == access("pre-receive", F_OK)) {
+        if (0 != unlink("pre-receive")) {
+            fprintf(stderr, "error: failed to remove old symlink "
+                "(%s/%s/hooks/pre-receive): %s\n", home, repo, strerror(errno));
+            rv = 1;
+            goto cleanup;
+        }
+    }
+
+    if (0 != symlink(self, "pre-receive")) {
+        fprintf(stderr, "error: failed to create symlink "
+            "(%s/%s/hooks/pre-receive): %s\n", home, repo, strerror(errno));
+        rv = 1;
+        goto cleanup;
+    }
+
+    if (0 == access("post-receive", F_OK)) {
+        if (0 != unlink("post-receive")) {
+            fprintf(stderr, "error: failed to remove old symlink "
+                "(%s/%s/hooks/post-receive): %s\n", home, repo, strerror(errno));
+            rv = 1;
+            goto cleanup;
+        }
+    }
+
+    if (0 != symlink(self, "post-receive")) {
+        fprintf(stderr, "error: failed to create symlink "
+            "(%s/%s/hooks/post-receive): %s\n", home, repo, strerror(errno));
+        rv = 1;
+        goto cleanup;
+    }
+
+    if (0 != chdir(home)) {
+        fprintf(stderr, "error: failed to chdir (%s): %s\n", home,
+            strerror(errno));
+        rv = 1;
+        goto cleanup;
+    }
+
+git_exec:
+    command_name = bc_strdup(argv[2]);
+    for (p = command_name; *p != ' ' && *p != '\0'; p++);
+    if (*p == ' ')
+        *p = '\0';
+
+    if (BUFFER_SIZE < (strlen(command_name) + strlen(repo) + 4)) {
+        fprintf(stderr, "error: git-shell command is too big\n");
+        rv = 1;
+        goto cleanup;
+    }
+
+    if (snprintf(command_new, BUFFER_SIZE, "%s '%s'", command_name, repo))
+        exec_git = true;
+
+cleanup:
+    free(repo);
+    free(command_orig);
+    free(command_name);
+
+    if (exec_git) {
+        execlp("git-shell", "git-shell", "-c", command_new, NULL);
+
+        // execlp only returns on error, then something bad happened
+        fprintf(stderr, "error: failed to execute git-shell\n");
+        rv = 1;
+    }
+
+    return rv;
+}