Implement hashing of username and password

src/userctl.c

@@ -1,7 +1,58 @@
 #include <stdio.h>
+#include <sha256.h>
+#define NOH_IMPLEMENTATION
+#include "noh.h"
+
+static void show_usage(char *program_name, char *error) {
+    noh_log(NOH_INFO, "Usage:");
+    noh_log(NOH_INFO, "%s username password", program_name);
+    noh_log(NOH_INFO, "  username: The username of the user to register.");
+    noh_log(NOH_INFO, "  password: The password of the user to register.");
+    noh_log(NOH_INFO, "");
+    noh_log(NOH_ERROR, "%s", error);
+    exit(1);
+}
+
+Noh_String hash_password(Noh_Arena *arena, Noh_String_View username, Noh_String_View password) {
+    // Build the sha input string.
+    Noh_String input = {0};
+    noh_string_append_sv(&input, username);
+    noh_string_append_cstr(&input, "<><>");
+    noh_string_append_sv(&input, password);
+
+    // Calculate the hash.
+    SHA256_CTX ctx = {0};
+    BYTE hash[32];
+    sha256_init(&ctx);
+    sha256_update(&ctx, (BYTE*)input.elems, input.count);
+    sha256_final(&ctx, hash);
+
+    // Build the result string.
+    noh_arena_save(arena);
+    Noh_String result = {0};
+    for (int i = 0; i < 32; i++) {
+        noh_string_append_cstr(&result, noh_arena_sprintf(arena, "%02x", hash[i]));
+    }
+    noh_arena_reset(arena);
+
+    return result;
+}
+
+int main(int argc, char **argv) {
+    // Parse input parameters.
+    char *program_name = noh_shift_args(&argc, &argv);
+
+    if (argc < 1) show_usage(program_name, "Username not provided.");
+    Noh_String_View username = noh_sv_from_cstr(noh_shift_args(&argc, &argv));
+
+    if (argc < 1) show_usage(program_name, "Password not provided.");
+    Noh_String_View password = noh_sv_from_cstr(noh_shift_args(&argc, &argv));
+
+    Noh_Arena arena = noh_arena_init(64 KB);
+    Noh_String result = hash_password(&arena, username, password);
+    noh_string_append_null(&result);
+    printf("%s\n", result.elems);
 
-int main() {
-    printf("Hello, world!\n");
     return 0;
 }