Argument parsing

src/util.c

@@ -0,0 +1,35 @@
+#include "util.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define DEFAULT_EXEC_NAME "httpserver"
+
+const char *EXEC_NAME = DEFAULT_EXEC_NAME;
+static bool need_free_out_of_memory_msg = false;
+NO_SANITIZE
+static const char *out_of_memory_msg =
+    DEFAULT_EXEC_NAME ": error: out of memory\n";
+
+void set_exec_name(const char *argv0) {
+    const char *slash = strrchr(argv0, '/');
+    if (!slash) {
+        EXEC_NAME = argv0;
+    } else {
+        EXEC_NAME = slash + 1;
+    }
+    if (need_free_out_of_memory_msg) {
+        free((char *) out_of_memory_msg);
+    }
+}
+
+void log_error(const char *fmt, ...) {
+    fprintf(stderr, "%s: error: ", EXEC_NAME);
+    va_list args;
+    va_start(args, fmt);
+    vfprintf(stderr, fmt, args);
+    va_end(args);
+    fputc('\n', stderr);
+}