ALPHA: URL parser

source/uselesshttpd/util.d

@@ -0,0 +1,177 @@
+module uselesshttpd.util;
+
+/*
+    lost+skunk <git.macaw.me/skunky>, 2025;
+    Licensed under WTFPL
+*/
+
+char[] intToStr(T)(T num) {
+    char[] buf;
+    for(short i; num > 0; ++i) {
+        buf = (num % 10 + '0')~buf;
+        num /= 10;
+    }
+    return buf;
+}
+
+void err(int e, string msg) {
+    if (e != 0)
+        throw new Exception("Something went wrong: failed to "~msg~'.');
+}
+
+// UDA
+struct Location { string path; }
+// enum method;
+
+string getStatus(short status) {
+    static foreach(mmbr; __traits(allMembers, Statuses))
+        if (__traits(getMember, Statuses, mmbr) == status)
+            return __traits(getAttributes, __traits(getMember, Statuses, mmbr))[0];
+    return "WTF";
+}
+
+// FIXME: memory leak
+void append(char[]* src, char symb) @nogc {
+    import core.memory: pureMalloc, pureFree;
+    auto arr = 
+        cast (char[])
+        pureMalloc(src.length + 1)
+        [0..src.length + 1];
+
+    arr[$-1..$] = symb;
+    arr[0..$-1] = *src;
+    *src = arr;
+
+    arr = null;
+    pureFree(arr.ptr);
+}
+
+void parseAndValidateURL(char[] url, Request* rqst) {
+    if (url.length > 2048) throw new Exception("Too long URL");
+    rqst.path = null;
+    bool notArgumentPart;
+    scope (exit) append(&rqst.args, '&');
+    for (short i; i < url.length; ++i) {
+        switch (url[i]) {
+            case '?':
+                if (notArgumentPart) goto default;
+                notArgumentPart = true;
+                break;
+            case '/':
+                if (url.length > i+1 && url[i+1] != '/') append(&rqst.path, '/');
+                break;
+            case '=', '&':
+                if (notArgumentPart && url[i-1] != url[i]) append(&rqst.args, url[i]);
+                break;
+
+            case 'A': .. case 'Z':
+            case 'a': .. case 'z':
+            case '0': .. case '9':
+            case '-', '_', '.', '~', '!', '$', '\'', '(', ')', '*', '+', ',', ';', '@', '[', ']', '|', '%':
+                if (notArgumentPart) append(&rqst.args, url[i]);
+                else append(&rqst.path, url[i]);
+                break;
+            default: throw new Exception("Malformed URL");
+        }
+    }
+}
+
+struct Request {
+    enum Methods {
+        GET = "GET",
+        PUT = "PUT",
+        POST = "POST",
+        DELETE = "DELETE",
+        OPTIONS = "OPTIONS",
+        // остальное лень реализовывать, да и не трэба..
+    }
+
+    Methods method;
+    void[] body;
+    string[string] headers;
+    
+    char[] path;
+    char[] args;
+    char[] getArgument(string arg) @nogc nothrow {
+        short split, prev;
+        for (short i; i < args.length; ++i) {
+            if (args[i] == '=') split = i;
+            else if (args[i] == '&') {
+                if (arg == args[prev..split]) return args[split+1..i];
+                prev = ++i;
+            }
+        }
+        return null;
+    }
+}
+
+private static enum Statuses: short { // спизженно с https://github.com/zigzap/zap/blob/675c65b509d48c21a8d1fa4c5ec53fc407643a3b/src/http.zig#L6
+    // Information responses
+    @("Continue") continuee = 100,
+    @("Switching Protocols") switching_protocols = 101,
+    @("Processing") processing = 102, // (WebDAV)
+    @("Early Hints") early_hints = 103,
+
+    // Successful responses
+    @("OK") ok = 200,
+    @("Created") created = 201,
+    @("Accepted") accepted = 202,
+    @("Non-Authoritative Information") non_authoritative_information = 203,
+    @("No Content") no_content = 204,
+    @("Reset Content") reset_content = 205,
+    @("Partial Content") partial_content = 206,
+    @("Multi-Status") multi_status = 207, // (WebDAV)
+    @("Already Reported") already_reported = 208, // (WebDAV)
+    @("IM Used") im_used = 226, // (HTTP Delta encoding)
+
+    // Redirection messages
+    @("Multiple Choices") multiple_choices = 300,
+    @("Moved Permanently") moved_permanently = 301,
+    @("Found") found = 302,
+    @("See Other") see_other = 303,
+    @("Not Modified") not_modified = 304,
+    @("Use Proxy") use_proxy = 305,
+    @("Unused") unused = 306,
+    @("Temporary Redirect") temporary_redirect = 307,
+    @("Permanent Redirect") permanent_redirect = 308,
+
+    // Client error responses
+    @("Bad Request") bad_request = 400,
+    @("Unauthorized") unauthorized = 401,
+    @("Payment Required") payment_required = 402,
+    @("Forbidden") forbidden = 403,
+    @("Not Found") not_found = 404,
+    @("Method Not Allowed") method_not_allowed = 405,
+    @("Not Acceptable") not_acceptable = 406,
+    @("Proxy Authentication Required") proxy_authentication_required = 407,
+    @("Request Timeout") request_timeout = 408,
+    @("Conflict") conflict = 409,
+    @("Gone") gone = 410,
+    @("Length Required") length_required = 411,
+    @("Precondition Failed") precondition_failed = 412,
+    @("Payload Too Large") payload_too_large = 413,
+    @("URI Too Long") uri_too_long = 414,
+    @("Unsupported Media Type") unsupported_media_type = 415,
+    @("Range Not Satisfiable") range_not_satisfiable = 416,
+    @("Expectation Failed") expectation_failed = 417,
+    @("I'm a teapot") im_a_teapot = 418,
+    @("Misdirected Request") misdirected_request = 421,
+    @("Unprocessable Content") unprocessable_content = 422, // (WebDAV)
+    @("Locked") locked = 423, // (WebDAV)
+    @("Failed Dependency") failed_dependency = 424, // (WebDAV)
+    @("Too Early") too_early = 425,
+    @("Upgrade Required") upgrade_required = 426,
+    @("Precondition Required") precondition_required = 428,
+    @("Too Many Requests") too_many_requests = 429,
+    @("Request Header Fields Too Large") request_header_fields_too_large = 431,
+    @("Unavailable For Legal Reasons") unavailable_for_legal_reasons = 451,
+
+    // Server error responses
+    @("Internal Server Error") internal_server_error = 500,
+    @("Not Implemented") not_implemented = 501,
+    @("Bad Gateway") bad_gateway = 502,
+    @("Service Unavailable") service_unavailable = 503,
+    @("Gateway Timeout") gateway_timeout = 504,
+    @("HTTP Version Not Supported") http_version_not_supported = 505,
+    @("Variant Also Negotiates") variant_also_negotiates = 506
+}