Function HandleClient

src/platform/win/http_server.cpp:184–440

handle one accepted connection: parse request line, dispatch GET or PUT

// handle one accepted connection: parse request line, dispatch GET or PUT
static void HandleClient(SOCKET client) {
    // Read headers until \r\n\r\n; cap at 64KB.
    static constexpr int MAX_HEADER_SIZE = 65536;
    std::vector<char> bufVec(MAX_HEADER_SIZE + 1);
    char* buf = bufVec.data();
    int total = 0;
    int headerEnd = -1;

    while (total < MAX_HEADER_SIZE) {
        int n = recv(client, buf + total, MAX_HEADER_SIZE - total, 0);
        if (n <= 0) break;
        total += n;
        buf[total] = '\0';

        char* found = strstr(buf, "\r\n\r\n");
        if (found) {
            headerEnd = (int)(found - buf) + 4;
            break;
        }
    }

    if (headerEnd < 0) {
        closesocket(client);
        return;
    }

    // parse request line: "METHOD /path HTTP/1.1\r\n"
    char method[16] = {};
    char path[2048] = {};
    if (sscanf(buf, "%15s %2047s", method, path) != 2) {
        closesocket(client);
        return;
    }

    // parse Content-Length from headers (case-insensitive)
    int64_t contentLength = -1;
    // Only search within header portion (before \r\n\r\n)
    const char* cl = stristr(buf, "\r\nContent-Length:");
    if (!cl || cl - buf > headerEnd) cl = nullptr;
    if (!cl) {
        cl = stristr(buf, "\nContent-Length:");
        if (cl && cl - buf > headerEnd) cl = nullptr;
    }
    if (cl) {
        char* endptr = nullptr;
        contentLength = _strtoi64(cl + (cl[0] == '\r' ? 17 : 16), &endptr, 10);
        if (endptr == cl + (cl[0] == '\r' ? 17 : 16)) contentLength = -1;
        if (contentLength < 0) contentLength = 0;
    }

    int bodyReceived = total - headerEnd;

    if (_stricmp(method, "PUT") == 0) {
        // Steam omits Content-Length for 0-byte files (LOCK, empty .log, etc.).
        // Treat missing header as 0 bytes rather than rejecting.
        if (contentLength < 0)
            contentLength = 0;