feat: add simple getopt cli

src/main.c

@@ -1,5 +1,64 @@
 #include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <getopt.h>
+
+struct cli_options {
+    int verbosity;
+    bool help;
+    bool version;
+};
+
+struct cli_options new_options() {
+    struct cli_options result;
+    result.verbosity = 0;
+    result.help = false;
+    return result;
+}
+
+//                                                         <max
+char* help_msg = 
+    "Usage: %s [-v level] [-h] [-V]\n"
+    "\n"
+    SCI_NAME " is a simple contiuous integration system.\n"
+    "\n"
+    "OPTIONS:\n"
+    "  -v level    Set verbosity level [0-3]\n"
+    "  -h          Show this message and exit\n"
+    "  -V          Show version and exit\n"
+    ;
+//                                                         <max
+
+void print_help(FILE * out, char* prog_name) {
+    fprintf(out, help_msg, prog_name);
+}
 
 int main(int argc, char** argv) {
-    printf("Hello, World!\n");
+    struct cli_options options = new_options();
+    int opt;
+    while((opt = getopt(argc, argv, "v:hV")) != -1) {
+        switch(opt) {
+            case 'v':
+                options.verbosity = atoi(optarg);
+                break;
+            case 'V':
+                options.version = true;
+                break;
+            case 'h':
+                options.help = true;
+                break;
+            default: // '?'
+                print_help(stderr, argv[0]);
+                exit(EXIT_FAILURE);
+        }
+    }
+    if(options.help) {
+        print_help(stdout, argv[0]);
+        exit(EXIT_SUCCESS);
+    }
+    if(options.version) {
+        fprintf(stdout, SCI_VERSION "\n");
+        exit(EXIT_SUCCESS);
+    }
 }