feat: add github-commits

github-commits/main.c

@@ -0,0 +1,180 @@
+/*
+ * Copyright (c) 2009-2016 Petri Lehtinen <petri@digip.org>
+ *
+ * Jansson is free software; you can redistribute it and/or modify
+ * it under the terms of the MIT license. See LICENSE for details.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include <curl/curl.h>
+#include <jansson.h>
+
+#define BUFFER_SIZE (256 * 1024) /* 256 KB */
+
+#define URL_FORMAT "https://api.github.com/repos/%s/%s/commits"
+#define URL_SIZE   256
+
+/* Return the offset of the first newline in text or the length of
+   text if there's no newline */
+static int newline_offset(const char *text) {
+    const char *newline = strchr(text, '\n');
+    if (!newline)
+        return strlen(text);
+    else
+        return (int)(newline - text);
+}
+
+struct write_result {
+    char *data;
+    int pos;
+};
+
+static size_t write_response(void *ptr, size_t size, size_t nmemb, void *stream) {
+    struct write_result *result = (struct write_result *)stream;
+
+    if (result->pos + size * nmemb >= BUFFER_SIZE - 1) {
+        fprintf(stderr, "error: too small buffer\n");
+        return 0;
+    }
+
+    memcpy(result->data + result->pos, ptr, size * nmemb);
+    result->pos += size * nmemb;
+
+    return size * nmemb;
+}
+
+static char *request(const char *url) {
+    CURL *curl = NULL;
+    CURLcode status;
+    struct curl_slist *headers = NULL;
+    char *data = NULL;
+    long code;
+
+    curl_global_init(CURL_GLOBAL_ALL);
+    curl = curl_easy_init();
+    if (!curl)
+        goto error;
+
+    data = malloc(BUFFER_SIZE);
+    if (!data)
+        goto error;
+
+    struct write_result write_result = {.data = data, .pos = 0};
+
+    curl_easy_setopt(curl, CURLOPT_URL, url);
+
+    /* GitHub commits API v3 requires a User-Agent header */
+    headers = curl_slist_append(headers, "User-Agent: Jansson-Tutorial");
+    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
+
+    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_response);
+    curl_easy_setopt(curl, CURLOPT_WRITEDATA, &write_result);
+
+    status = curl_easy_perform(curl);
+    if (status != 0) {
+        fprintf(stderr, "error: unable to request data from %s:\n", url);
+        fprintf(stderr, "%s\n", curl_easy_strerror(status));
+        goto error;
+    }
+
+    curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &code);
+    if (code != 200) {
+        fprintf(stderr, "error: server responded with code %ld\n", code);
+        goto error;
+    }
+
+    curl_easy_cleanup(curl);
+    curl_slist_free_all(headers);
+    curl_global_cleanup();
+
+    /* zero-terminate the result */
+    data[write_result.pos] = '\0';
+
+    return data;
+
+error:
+    if (data)
+        free(data);
+    if (curl)
+        curl_easy_cleanup(curl);
+    if (headers)
+        curl_slist_free_all(headers);
+    curl_global_cleanup();
+    return NULL;
+}
+
+int main(int argc, char *argv[]) {
+    size_t i;
+    char *text;
+    char url[URL_SIZE];
+
+    json_t *root;
+    json_error_t error;
+
+    if (argc != 3) {
+        fprintf(stderr, "usage: %s USER REPOSITORY\n\n", argv[0]);
+        fprintf(stderr, "List commits at USER's REPOSITORY.\n\n");
+        return 2;
+    }
+
+    snprintf(url, URL_SIZE, URL_FORMAT, argv[1], argv[2]);
+
+    text = request(url);
+    if (!text)
+        return 1;
+
+    root = json_loads(text, 0, &error);
+    free(text);
+
+    if (!root) {
+        fprintf(stderr, "error: on line %d: %s\n", error.line, error.text);
+        return 1;
+    }
+
+    if (!json_is_array(root)) {
+        fprintf(stderr, "error: root is not an array\n");
+        json_decref(root);
+        return 1;
+    }
+
+    for (i = 0; i < json_array_size(root); i++) {
+        json_t *data, *sha, *commit, *message;
+        const char *message_text;
+
+        data = json_array_get(root, i);
+        if (!json_is_object(data)) {
+            fprintf(stderr, "error: commit data %d is not an object\n", (int)(i + 1));
+            json_decref(root);
+            return 1;
+        }
+
+        sha = json_object_get(data, "sha");
+        if (!json_is_string(sha)) {
+            fprintf(stderr, "error: commit %d: sha is not a string\n", (int)(i + 1));
+            return 1;
+        }
+
+        commit = json_object_get(data, "commit");
+        if (!json_is_object(commit)) {
+            fprintf(stderr, "error: commit %d: commit is not an object\n", (int)(i + 1));
+            json_decref(root);
+            return 1;
+        }
+
+        message = json_object_get(commit, "message");
+        if (!json_is_string(message)) {
+            fprintf(stderr, "error: commit %d: message is not a string\n", (int)(i + 1));
+            json_decref(root);
+            return 1;
+        }
+
+        message_text = json_string_value(message);
+        printf("%.8s %.*s\n", json_string_value(sha), newline_offset(message_text),
+               message_text);
+    }
+
+    json_decref(root);
+    return 0;
+}

github-commits/makefile

@@ -0,0 +1,24 @@
+# Docu
+#
+#$@ is the name of the file to be made
+#$? is the names of the changed dependents
+#$< the name of the related file that caused the action
+#$* the prefix shared by target and dependent files
+#
+# Others
+RM      = /bin/rm -f
+#
+# Source, Executable, Includes, Library Defines
+EXE    = main
+#
+# Compiler, Linker Defines
+CC      = /usr/bin/gcc
+#
+all: main.o
+	$(CC) main.c -L/usr/lib/x86_64-linux-gnu -lcurl -ljansson -Wall -o $(EXE)
+#
+main.o:
+	$(CC) -c main.c
+# Clean Up Objects, Exectuables, Dumps out of source directory
+clean:
+	$(RM) *.o $(EXE) *~

github-commits/readme.md

@@ -0,0 +1,17 @@
+* build
+
+```
+make clean all
+```
+
+* cleanup
+
+```
+make clean
+```
+
+* run
+
+```
+./main <user> <repository>
+```