support native plugin

.github/workflows/payload.yml

@@ -28,11 +28,17 @@ jobs:
       run: |
         make clean all PS5_PAYLOAD_SDK=/opt/ps5-payload-sdk
 
+    - name: Build demo plugin
+      run: |
+        cd plugin/demo && make clean all PS5_PAYLOAD_SDK=/opt/ps5-payload-sdk
+
     - name: Upload
       uses: actions/upload-artifact@v4
       with:
         name: Payload
-        path: websrv-ps5.elf
+        path: |
+          websrv-ps5.elf
+          plugin/demo/demo.so
         if-no-files-found: error
 
   release:

Makefile.pc

@@ -19,11 +19,12 @@ VERSION_TAG := $(shell git describe --abbrev=10 --dirty --always --tags)
 PYTHON ?= python3
 
 BIN   := websrv.pc
-SRCS   := src/main.c src/websrv.c src/asset.c src/fs.c src/mime.c
+SRCS   := src/main.c src/websrv.c src/asset.c src/fs.c src/mime.c src/plugin.c
 SRCS   += src/pc/sys.c
 
 CFLAGS := -Wall -DVERSION_TAG=\"$(VERSION_TAG)\"
 LDADD  += `pkg-config libmicrohttpd --libs`
+LDADD  += -ldl
 
 ASSETS   := $(wildcard assets/*)
 GEN_SRCS := $(patsubst assets/%,gen/%, $(ASSETS:=.c))

Makefile.ps5

@@ -29,7 +29,7 @@ PYTHON ?= python3
 
 BIN    := websrv-ps5.elf
 
-SRCS   := src/main.c src/websrv.c src/asset.c src/fs.c src/mime.c
+SRCS   := src/main.c src/websrv.c src/asset.c src/fs.c src/mime.c src/plugin.c
 SRCS   += src/mdns.c src/smb.c
 SRCS   += src/ps5/sys.c src/ps5/pt.c src/ps5/elfldr.c src/ps5/hbldr.c
 SRCS   += src/ps5/notify.c src/ps5/http.c

README.md

@@ -28,6 +28,8 @@ Examples:
 - http://ps5:8080/smb?addr=192.168.1.1 - List shares on a remote SMB host (json)
 - http://ps5:8080/smb/share?addr=192.168.1.1 - List files and folders shared by a remote SMB host (json)
 - http://ps5:8080/smb/share/file?addr=192.168.1.1 - Download a remote SMB file via websrv
+- http://ps5:8080/plugin - List loaded native plugins (html)
+- http://ps5:8080/plugin/demo - Example native plugin (if installed)
 
 ## Installing Homebrew
 The web server will search for homebrew in /data/homebrew, /mnt/usb%d/homebrew, /mnt/ext%d/homebrew,
@@ -48,6 +50,41 @@ For real-world homebrew, checkout:
 - https://github.com/ps5-payload-dev/websrv/releases
 - https://github.com/cy33hc/ps5-ezremote-client
 
+## Native plugins
+websrv can load native plugins from shared objects (`.so` files) placed under
+`/data/homebrew/websrv/plugin` (and the same `homebrew/websrv/plugin` path on
+USB/external volumes). Each plugin is a shared object named `<soname>.so` and
+must export:
+
+- `<soname>_plugin_register_url()` — returns the URL prefix without a leading
+  slash, e.g. `"plugin/demo"` (serves `http://ps5:8080/plugin/demo` and
+  sub-paths).
+- `<soname>_plugin_handle_request()` — handles HTTP requests routed to that
+  prefix. Receives a per-request `plugin_context_t` (`void*`, the host
+  `MHD_Connection`), parsed POST fields as a `plugin_post_data_t` list (NULL for
+  GET/HEAD), and a `plugin_response_fn` callback. Call `respond(ctx, resp)` to
+  send a response (the host copies the body before the callback returns); both
+  `respond` and `handle_request` return **0 on success**. Return non-zero from
+  `handle_request` if the request is not handled. Release per-request buffers
+  after `respond` returns. Plugins need only [src/plugin_api.h](src/plugin_api.h),
+  not libmicrohttpd.
+
+For `demo.so`, the symbols are `demo_plugin_register_url` and
+`demo_plugin_handle_request`.
+
+See [src/plugin_api.h](src/plugin_api.h) and the example in
+[plugin/demo](plugin/demo). Build the demo plugin with:
+
+```console
+john@localhost:websrv/plugin/demo$ export PS5_PAYLOAD_SDK=/opt/ps5-payload-sdk
+john@localhost:websrv/plugin/demo$ make
+john@localhost:websrv/plugin/demo$ mkdir -p /data/homebrew/websrv/plugin/demo
+john@localhost:websrv/plugin/demo$ cp demo.so /data/homebrew/websrv/plugin/demo/
+```
+
+Restart or reload websrv; matching requests are dispatched to the plugin
+instead of the built-in static assets.
+
 ## Building
 Assuming you have the [packbrew][packbrew] SDK installed on a Debian-flavored
 operating system, the payload can be compiled using the following commands:

assets/index.html

@@ -125,6 +125,14 @@
         </symbol>
     </svg>
 
+    <header class="header">
+        <p>
+            <a href="/fs/">Filesystem</a>
+            &middot;
+            <a href="/plugin">Plugins</a>
+        </p>
+    </header>
+
     <!-- router relies on the div with id="content" -->
     <!-- <div class="container" id="content"> 
     </div> -->

assets/main.css

@@ -84,15 +84,32 @@ body {
 }
 
 .header {
+    position: fixed;
+    top: 0;
+    left: 0;
+    right: 0;
+    z-index: 100;
     text-align: center;
-    margin-top: 2rem;
+    margin-top: 0.75rem;
+    pointer-events: none;
 }
 
 .header * {
     margin: 0;
     padding: 0;
 }
 
+.header a {
+    pointer-events: auto;
+    color: var(--secondary-text-color);
+    text-decoration: none;
+}
+
+.header a:hover {
+    color: var(--text-color);
+    text-decoration: underline;
+}
+
 div.carousel {
     padding: 0 512px;
     height: 100vh;

plugin/demo/Makefile

@@ -0,0 +1,32 @@
+#   Copyright (C) 2025 John Törnblom
+#
+# This file is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+
+ifdef PS5_PAYLOAD_SDK
+    include $(PS5_PAYLOAD_SDK)/toolchain/prospero.mk
+else
+    CC ?= gcc
+endif
+
+WEBSRV_SRC := ../../src
+CFLAGS += -I$(WEBSRV_SRC) -fPIC -shared -Wall -Werror
+PLUGIN := demo.so
+
+all: $(PLUGIN)
+
+install: $(PLUGIN)
+	mkdir -p ../../plugin/demo
+	@if ! cmp -s $(PLUGIN) ../../plugin/demo/$(PLUGIN) 2>/dev/null; then \
+	  cp -f $(PLUGIN) ../../plugin/demo/; \
+	fi
+
+$(PLUGIN): demo.c
+	$(CC) $(CFLAGS) -o $@ $^
+
+clean:
+	rm -f $(PLUGIN)
+
+.PHONY: all install clean

plugin/demo/demo.c

@@ -0,0 +1,184 @@
+/* Copyright (C) 2025 John Törnblom
+
+This program is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 3, or (at your option) any
+later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; see the file COPYING. If not, see
+<http://www.gnu.org/licenses/>.  */
+
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+
+#include "plugin_api.h"
+
+
+#define DEMO_CTX_SLOTS 64
+
+
+static const char PAGE[] =
+  "<html><head><title>websrv plugin demo</title></head>"
+  "<body>"
+  "<h1>plugin/demo</h1>"
+  "<form method=\"POST\">"
+  "<label>msg <input name=\"msg\" value=\"hello\"></label>"
+  "<button type=\"submit\">POST</button>"
+  "</form>"
+  "</body></html>";
+
+static const char BODY_429[] = "Too Many Requests";
+
+
+typedef struct demo_request_state {
+  plugin_context_t ctx;
+  plugin_response_header_t hdr;
+  plugin_response_data_t resp;
+  char json_body[4096];
+} demo_request_state_t;
+
+
+static demo_request_state_t g_demo_state[DEMO_CTX_SLOTS];
+
+
+static demo_request_state_t*
+demo_state_for(plugin_context_t ctx) {
+  size_t i;
+  demo_request_state_t* free_slot = 0;
+
+  for(i=0; i<DEMO_CTX_SLOTS; i++) {
+    if(g_demo_state[i].ctx == ctx) {
+      return &g_demo_state[i];
+    }
+    if(!free_slot && !g_demo_state[i].ctx) {
+      free_slot = &g_demo_state[i];
+    }
+  }
+
+  if(!free_slot) {
+    return 0;
+  }
+
+  free_slot->ctx = ctx;
+  return free_slot;
+}
+
+
+static void
+demo_state_release(plugin_context_t ctx) {
+  size_t i;
+
+  for(i=0; i<DEMO_CTX_SLOTS; i++) {
+    if(g_demo_state[i].ctx == ctx) {
+      memset(&g_demo_state[i], 0, sizeof(g_demo_state[i]));
+      return;
+    }
+  }
+}
+
+
+static plugin_response_data_t*
+demo_build_response(demo_request_state_t* state, int status,
+                    const char* mime, const uint8_t* body, size_t body_len) {
+  state->hdr.key = "Content-Type";
+  state->hdr.val = mime;
+  state->hdr.next = 0;
+
+  state->resp.status = status;
+  state->resp.headers = &state->hdr;
+  state->resp.body = body;
+  state->resp.body_len = body_len;
+  return &state->resp;
+}
+
+
+static plugin_response_data_t*
+demo_too_many_requests(void) {
+  static plugin_response_header_t hdr;
+  static plugin_response_data_t resp;
+
+  hdr.key = "Content-Type";
+  hdr.val = "text/plain";
+  hdr.next = 0;
+  resp.status = PLUGIN_HTTP_TOO_MANY_REQUESTS;
+  resp.headers = &hdr;
+  resp.body = (const uint8_t*)BODY_429;
+  resp.body_len = sizeof(BODY_429) - 1;
+  return &resp;
+}
+
+
+const char*
+demo_plugin_register_url(void) {
+  return "plugin/demo";
+}
+
+
+int
+demo_plugin_handle_request(plugin_context_t ctx, const char* url,
+                           const char* method, const plugin_post_data_t* post,
+                           plugin_response_fn respond) {
+  demo_request_state_t* state;
+  size_t len;
+  int first;
+  int ret;
+
+  (void)url;
+
+  state = demo_state_for(ctx);
+  if(!state) {
+    return respond(ctx, demo_too_many_requests());
+  }
+
+  if(!strcmp(method, PLUGIN_METHOD_GET) ||
+     !strcmp(method, PLUGIN_METHOD_HEAD)) {
+    ret = respond(ctx, demo_build_response(state, PLUGIN_HTTP_OK, "text/html",
+                                           (const uint8_t*)PAGE,
+                                           sizeof(PAGE) - 1));
+    demo_state_release(ctx);
+    return ret;
+  }
+
+  if(!strcmp(method, PLUGIN_METHOD_POST)) {
+    first = 1;
+    len = snprintf(state->json_body, sizeof(state->json_body),
+                   "{\"ctx\":%" PRId64 ",\"fields\":{",
+                   (int64_t)(intptr_t)ctx);
+    for(; post && len < sizeof(state->json_body) - 64; post=post->next) {
+      if(!first) {
+        len += snprintf(state->json_body + len,
+                        sizeof(state->json_body) - len, ",");
+      }
+      first = 0;
+      len += snprintf(state->json_body + len,
+                      sizeof(state->json_body) - len,
+                      "\"%s\":\"", post->key);
+      if(post->val && post->len) {
+        len += snprintf(state->json_body + len,
+                        sizeof(state->json_body) - len, "%.*s",
+                        (int)post->len, (const char*)post->val);
+      }
+      len += snprintf(state->json_body + len,
+                      sizeof(state->json_body) - len, "\"");
+    }
+    len += snprintf(state->json_body + len,
+                    sizeof(state->json_body) - len, "}}");
+    ret = respond(ctx, demo_build_response(state, PLUGIN_HTTP_OK,
+                                           "application/json",
+                                           (const uint8_t*)state->json_body,
+                                           len));
+    demo_state_release(ctx);
+    return ret;
+  }
+
+  demo_state_release(ctx);
+  return 1;
+}