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Merged
mathieucarbou merged 2 commits into from
Jan 22, 2026
Merged

Store HTTP response strings in PROGMEM on ESP8266 #372

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8d3e320
Store HTTP response strings in PROGMEM on ESP8266
bdraco Jan 22, 2026
a6649d3
ci(pre-commit): Apply automatic fixes
pre-commit-ci-lite[bot] Jan 22, 2026
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3 changes: 2 additions & 1 deletion src/ESPAsyncWebServer.h
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Original file line number Diff line number Diff line change
Expand Up @@ -1367,7 +1367,8 @@ class AsyncWebServerResponse {
static bool headerMustBePresentOnce(const String &name);

public:
static const char *responseCodeToString(int code);
// Return type changes based on platform (const char* or __FlashStringHelper*)
static STR_RETURN_TYPE responseCodeToString(int code);

public:
AsyncWebServerResponse();
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86 changes: 43 additions & 43 deletions src/WebResponses.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -25,50 +25,50 @@ using namespace asyncsrv;
*
*/

const char *AsyncWebServerResponse::responseCodeToString(int code) {
STR_RETURN_TYPE AsyncWebServerResponse::responseCodeToString(int code) {
switch (code) {
case 100: return T_HTTP_CODE_100;
case 101: return T_HTTP_CODE_101;
case 200: return T_HTTP_CODE_200;
case 201: return T_HTTP_CODE_201;
case 202: return T_HTTP_CODE_202;
case 203: return T_HTTP_CODE_203;
case 204: return T_HTTP_CODE_204;
case 205: return T_HTTP_CODE_205;
case 206: return T_HTTP_CODE_206;
case 300: return T_HTTP_CODE_300;
case 301: return T_HTTP_CODE_301;
case 302: return T_HTTP_CODE_302;
case 303: return T_HTTP_CODE_303;
case 304: return T_HTTP_CODE_304;
case 305: return T_HTTP_CODE_305;
case 307: return T_HTTP_CODE_307;
case 400: return T_HTTP_CODE_400;
case 401: return T_HTTP_CODE_401;
case 402: return T_HTTP_CODE_402;
case 403: return T_HTTP_CODE_403;
case 404: return T_HTTP_CODE_404;
case 405: return T_HTTP_CODE_405;
case 406: return T_HTTP_CODE_406;
case 407: return T_HTTP_CODE_407;
case 408: return T_HTTP_CODE_408;
case 409: return T_HTTP_CODE_409;
case 410: return T_HTTP_CODE_410;
case 411: return T_HTTP_CODE_411;
case 412: return T_HTTP_CODE_412;
case 413: return T_HTTP_CODE_413;
case 414: return T_HTTP_CODE_414;
case 415: return T_HTTP_CODE_415;
case 416: return T_HTTP_CODE_416;
case 417: return T_HTTP_CODE_417;
case 429: return T_HTTP_CODE_429;
case 500: return T_HTTP_CODE_500;
case 501: return T_HTTP_CODE_501;
case 502: return T_HTTP_CODE_502;
case 503: return T_HTTP_CODE_503;
case 504: return T_HTTP_CODE_504;
case 505: return T_HTTP_CODE_505;
default: return T_HTTP_CODE_ANY;
case 100: return STR(T_HTTP_CODE_100);
case 101: return STR(T_HTTP_CODE_101);
case 200: return STR(T_HTTP_CODE_200);
case 201: return STR(T_HTTP_CODE_201);
case 202: return STR(T_HTTP_CODE_202);
case 203: return STR(T_HTTP_CODE_203);
case 204: return STR(T_HTTP_CODE_204);
case 205: return STR(T_HTTP_CODE_205);
case 206: return STR(T_HTTP_CODE_206);
case 300: return STR(T_HTTP_CODE_300);
case 301: return STR(T_HTTP_CODE_301);
case 302: return STR(T_HTTP_CODE_302);
case 303: return STR(T_HTTP_CODE_303);
case 304: return STR(T_HTTP_CODE_304);
case 305: return STR(T_HTTP_CODE_305);
case 307: return STR(T_HTTP_CODE_307);
case 400: return STR(T_HTTP_CODE_400);
case 401: return STR(T_HTTP_CODE_401);
case 402: return STR(T_HTTP_CODE_402);
case 403: return STR(T_HTTP_CODE_403);
case 404: return STR(T_HTTP_CODE_404);
case 405: return STR(T_HTTP_CODE_405);
case 406: return STR(T_HTTP_CODE_406);
case 407: return STR(T_HTTP_CODE_407);
case 408: return STR(T_HTTP_CODE_408);
case 409: return STR(T_HTTP_CODE_409);
case 410: return STR(T_HTTP_CODE_410);
case 411: return STR(T_HTTP_CODE_411);
case 412: return STR(T_HTTP_CODE_412);
case 413: return STR(T_HTTP_CODE_413);
case 414: return STR(T_HTTP_CODE_414);
case 415: return STR(T_HTTP_CODE_415);
case 416: return STR(T_HTTP_CODE_416);
case 417: return STR(T_HTTP_CODE_417);
case 429: return STR(T_HTTP_CODE_429);
case 500: return STR(T_HTTP_CODE_500);
case 501: return STR(T_HTTP_CODE_501);
case 502: return STR(T_HTTP_CODE_502);
case 503: return STR(T_HTTP_CODE_503);
case 504: return STR(T_HTTP_CODE_504);
case 505: return STR(T_HTTP_CODE_505);
default: return STR(T_HTTP_CODE_ANY);
}
}

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105 changes: 62 additions & 43 deletions src/literals.h
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Original file line number Diff line number Diff line change
Expand Up @@ -3,6 +3,25 @@

#pragma once

// Include WString.h for F() macro support on Arduino platforms
#ifdef ARDUINO
#include <WString.h>
#endif

// Platform-specific string storage and return type
#ifdef ARDUINO_ARCH_ESP8266
// On ESP8266, use PROGMEM storage and return __FlashStringHelper*
#include <pgmspace.h>
#define DECLARE_STR(name, value) static const char name##_PROGMEM[] PROGMEM = value
#define STR(name) (reinterpret_cast<const __FlashStringHelper *>(name##_PROGMEM))
#define STR_RETURN_TYPE const __FlashStringHelper *
#else
// On other platforms, use regular constexpr for compile-time optimization
#define DECLARE_STR(name, value) static constexpr const char *name = value
#define STR(name) name
#define STR_RETURN_TYPE const char *
#endif

namespace asyncsrv {

static constexpr const char empty[] = "";
Expand Down Expand Up @@ -154,49 +173,49 @@ static constexpr const char T_text_xml[] = "text/xml";
static constexpr const char T_video_mp4[] = "video/mp4";
static constexpr const char T_video_webm[] = "video/webm";

// Response codes
static constexpr const char T_HTTP_CODE_100[] = "Continue";
static constexpr const char T_HTTP_CODE_101[] = "Switching Protocols";
static constexpr const char T_HTTP_CODE_200[] = "OK";
static constexpr const char T_HTTP_CODE_201[] = "Created";
static constexpr const char T_HTTP_CODE_202[] = "Accepted";
static constexpr const char T_HTTP_CODE_203[] = "Non-Authoritative Information";
static constexpr const char T_HTTP_CODE_204[] = "No Content";
static constexpr const char T_HTTP_CODE_205[] = "Reset Content";
static constexpr const char T_HTTP_CODE_206[] = "Partial Content";
static constexpr const char T_HTTP_CODE_300[] = "Multiple Choices";
static constexpr const char T_HTTP_CODE_301[] = "Moved Permanently";
static constexpr const char T_HTTP_CODE_302[] = "Found";
static constexpr const char T_HTTP_CODE_303[] = "See Other";
static constexpr const char T_HTTP_CODE_304[] = "Not Modified";
static constexpr const char T_HTTP_CODE_305[] = "Use Proxy";
static constexpr const char T_HTTP_CODE_307[] = "Temporary Redirect";
static constexpr const char T_HTTP_CODE_400[] = "Bad Request";
static constexpr const char T_HTTP_CODE_401[] = "Unauthorized";
static constexpr const char T_HTTP_CODE_402[] = "Payment Required";
static constexpr const char T_HTTP_CODE_403[] = "Forbidden";
static constexpr const char T_HTTP_CODE_404[] = "Not Found";
static constexpr const char T_HTTP_CODE_405[] = "Method Not Allowed";
static constexpr const char T_HTTP_CODE_406[] = "Not Acceptable";
static constexpr const char T_HTTP_CODE_407[] = "Proxy Authentication Required";
static constexpr const char T_HTTP_CODE_408[] = "Request Time-out";
static constexpr const char T_HTTP_CODE_409[] = "Conflict";
static constexpr const char T_HTTP_CODE_410[] = "Gone";
static constexpr const char T_HTTP_CODE_411[] = "Length Required";
static constexpr const char T_HTTP_CODE_412[] = "Precondition Failed";
static constexpr const char T_HTTP_CODE_413[] = "Request Entity Too Large";
static constexpr const char T_HTTP_CODE_414[] = "Request-URI Too Large";
static constexpr const char T_HTTP_CODE_415[] = "Unsupported Media Type";
static constexpr const char T_HTTP_CODE_416[] = "Requested Range Not Satisfiable";
static constexpr const char T_HTTP_CODE_417[] = "Expectation Failed";
static constexpr const char T_HTTP_CODE_429[] = "Too Many Requests";
static constexpr const char T_HTTP_CODE_500[] = "Internal Server Error";
static constexpr const char T_HTTP_CODE_501[] = "Not Implemented";
static constexpr const char T_HTTP_CODE_502[] = "Bad Gateway";
static constexpr const char T_HTTP_CODE_503[] = "Service Unavailable";
static constexpr const char T_HTTP_CODE_504[] = "Gateway Time-out";
static constexpr const char T_HTTP_CODE_505[] = "HTTP Version Not Supported";
static constexpr const char T_HTTP_CODE_ANY[] = "Unknown code";
// Response codes - using DECLARE_STR macro for platform-specific storage
DECLARE_STR(T_HTTP_CODE_100, "Continue");
DECLARE_STR(T_HTTP_CODE_101, "Switching Protocols");
DECLARE_STR(T_HTTP_CODE_200, "OK");
DECLARE_STR(T_HTTP_CODE_201, "Created");
DECLARE_STR(T_HTTP_CODE_202, "Accepted");
DECLARE_STR(T_HTTP_CODE_203, "Non-Authoritative Information");
DECLARE_STR(T_HTTP_CODE_204, "No Content");
DECLARE_STR(T_HTTP_CODE_205, "Reset Content");
DECLARE_STR(T_HTTP_CODE_206, "Partial Content");
DECLARE_STR(T_HTTP_CODE_300, "Multiple Choices");
DECLARE_STR(T_HTTP_CODE_301, "Moved Permanently");
DECLARE_STR(T_HTTP_CODE_302, "Found");
DECLARE_STR(T_HTTP_CODE_303, "See Other");
DECLARE_STR(T_HTTP_CODE_304, "Not Modified");
DECLARE_STR(T_HTTP_CODE_305, "Use Proxy");
DECLARE_STR(T_HTTP_CODE_307, "Temporary Redirect");
DECLARE_STR(T_HTTP_CODE_400, "Bad Request");
DECLARE_STR(T_HTTP_CODE_401, "Unauthorized");
DECLARE_STR(T_HTTP_CODE_402, "Payment Required");
DECLARE_STR(T_HTTP_CODE_403, "Forbidden");
DECLARE_STR(T_HTTP_CODE_404, "Not Found");
DECLARE_STR(T_HTTP_CODE_405, "Method Not Allowed");
DECLARE_STR(T_HTTP_CODE_406, "Not Acceptable");
DECLARE_STR(T_HTTP_CODE_407, "Proxy Authentication Required");
DECLARE_STR(T_HTTP_CODE_408, "Request Time-out");
DECLARE_STR(T_HTTP_CODE_409, "Conflict");
DECLARE_STR(T_HTTP_CODE_410, "Gone");
DECLARE_STR(T_HTTP_CODE_411, "Length Required");
DECLARE_STR(T_HTTP_CODE_412, "Precondition Failed");
DECLARE_STR(T_HTTP_CODE_413, "Request Entity Too Large");
DECLARE_STR(T_HTTP_CODE_414, "Request-URI Too Large");
DECLARE_STR(T_HTTP_CODE_415, "Unsupported Media Type");
DECLARE_STR(T_HTTP_CODE_416, "Requested Range Not Satisfiable");
DECLARE_STR(T_HTTP_CODE_417, "Expectation Failed");
DECLARE_STR(T_HTTP_CODE_429, "Too Many Requests");
DECLARE_STR(T_HTTP_CODE_500, "Internal Server Error");
DECLARE_STR(T_HTTP_CODE_501, "Not Implemented");
DECLARE_STR(T_HTTP_CODE_502, "Bad Gateway");
DECLARE_STR(T_HTTP_CODE_503, "Service Unavailable");
DECLARE_STR(T_HTTP_CODE_504, "Gateway Time-out");
DECLARE_STR(T_HTTP_CODE_505, "HTTP Version Not Supported");
DECLARE_STR(T_HTTP_CODE_ANY, "Unknown code");

static constexpr const char *T_only_once_headers[] = {
T_Accept_Ranges, T_Content_Length, T_Content_Type, T_Connection, T_CORS_ACAC, T_CORS_ACAH, T_CORS_ACAM, T_CORS_ACAO,
Expand Down