feat: Implement basic introspection calls

src/lua_libpulse_glib/context.h

@@ -5,6 +5,7 @@
 #include "lauxlib.h"
 #include "pulse/context.h"
 #include "pulse/mainloop-api.h"
+#include "introspection.h"
 
 #define LUA_PA_CONTEXT "pulseaudio.context"
 
@@ -36,5 +37,8 @@ static const struct luaL_Reg context_mt [] = {
     {"__index", context__index},
     {"__gc", context__gc},
     {"connect", context_connect},
+    {"get_server_info", context_get_server_info},
+    {"get_sinks", context_get_sink_info_list},
+    {"get_sources", context_get_source_info_list},
     {NULL, NULL}
 };

src/lua_libpulse_glib/introspection.c

@@ -0,0 +1,281 @@
+#include <pulse/introspect.h>
+#include <pulse/error.h>
+#include "introspection.h"
+#include "context.h"
+#include "pulseaudio.h"
+
+
+// TODO: Figure out error handling for callbacks
+
+
+typedef struct server_info_callback_data {
+    lua_State* L;
+    int thread_ref;
+} server_info_callback_data;
+
+
+void
+server_info_to_lua(lua_State* L, const pa_server_info* info)
+{
+    lua_createtable(L, 0, 9);
+    int table_index = lua_gettop(L);
+
+    lua_pushstring(L, "user_name");
+    lua_pushstring(L, info->user_name);
+    lua_settable(L, table_index);
+
+    lua_pushstring(L, "host_name");
+    lua_pushstring(L, info->host_name);
+    lua_settable(L, table_index);
+
+    lua_pushstring(L, "server_version");
+    lua_pushstring(L, info->server_version);
+    lua_settable(L, table_index);
+
+    lua_pushstring(L, "server_name");
+    lua_pushstring(L, info->server_name);
+    lua_settable(L, table_index);
+
+    lua_pushstring(L, "default_sink_name");
+    lua_pushstring(L, info->default_sink_name);
+    lua_settable(L, table_index);
+
+    lua_pushstring(L, "cookie");
+    lua_pushinteger(L, info->cookie);
+    lua_settable(L, table_index);
+
+    // TODO: Handle `sample_spec` and `channel_map` tables
+}
+
+
+void
+server_info_callback(pa_context* c, const pa_server_info* info, void* userdata)
+{
+
+    server_info_callback_data* data = (server_info_callback_data*) userdata;
+    lua_State* L = data->L;
+
+    lua_pushnil(L);
+    server_info_to_lua(L, info);
+    lua_call(L, 2, 0);
+
+    // Remove thread reference
+    lua_pushstring(L, LUA_PULSEAUDIO);
+    lua_rawget(L, LUA_REGISTRYINDEX);
+    lua_pushstring(L, LUA_PA_REGISTRY);
+    lua_gettable(L, -2);
+    luaL_unref(L, -1, data->thread_ref);
+
+    free(data);
+}
+
+
+int
+context_get_server_info(lua_State* L)
+{
+    lua_pa_context* ctx = luaL_checkudata(L, 1, LUA_PA_CONTEXT);
+
+    if (pa_context_get_state(ctx->context) != PA_CONTEXT_READY) {
+        lua_pushvalue(L, 2);
+        lua_pushstring(L, "connection not ready");
+        lua_call(L, 1, 0);
+        return 0;
+    }
+
+    // Prepare a new thread to run the callback with
+    lua_pushstring(L, LUA_PULSEAUDIO);
+    lua_rawget(L, LUA_REGISTRYINDEX);
+    lua_pushstring(L, LUA_PA_REGISTRY);
+    lua_gettable(L, -2);
+    lua_State* thread = lua_newthread(L);
+    int thread_ref = luaL_ref(L, -2);
+
+    // Copy the callback function to the thread's stack
+    lua_pushvalue(L, 2);
+    lua_xmove(L, thread, 1);
+
+    server_info_callback_data* data = calloc(1, sizeof(struct server_info_callback_data));
+    data->L = thread;
+    data->thread_ref = thread_ref;
+
+    pa_operation* op = pa_context_get_server_info(ctx->context, server_info_callback, data);
+    if (op == NULL) {
+        int error = pa_context_errno(ctx->context);
+        lua_pushvalue(L, 2);
+        lua_pushfstring(L, "failed to get server info: %s", pa_strerror(error));
+        lua_call(L, 1, 0);
+        return 0;
+    }
+
+    return 0;
+}
+
+
+typedef struct sink_info_list_callback_data {
+    lua_State* L;
+    int thread_ref;
+} sink_info_list_callback_data;
+
+
+void
+sink_info_to_lua(lua_State* L, const pa_sink_info* info)
+{
+    lua_createtable(L, 0, 24);
+    int table_index = lua_gettop(L);
+
+    lua_pushstring(L, "name");
+    lua_pushstring(L, info->name);
+    lua_settable(L, table_index);
+
+    // TODO: Handle rest of the table
+}
+
+
+void
+sink_info_list_callback(pa_context* c, const pa_sink_info* info, int eol, void* userdata)
+{
+    sink_info_list_callback_data* data = (sink_info_list_callback_data*) userdata;
+    lua_State* L = data->L;
+
+    if (eol == 0) {
+        int i = lua_objlen(L, 2);
+        lua_pushinteger(L, i+1);
+        sink_info_to_lua(L, info);
+        lua_settable(L, 2);
+    } else {
+        // Insert the error argument
+        lua_pushnil(L);
+        lua_insert(L, -2);
+
+        lua_call(L, 2, 0);
+
+        lua_pushstring(L, LUA_PULSEAUDIO);
+        lua_rawget(L, LUA_REGISTRYINDEX);
+
+        lua_pushstring(L, LUA_PA_REGISTRY);
+        lua_gettable(L, -2);
+        luaL_unref(L, -1, data->thread_ref);
+        free(data);
+    }
+}
+
+
+int
+context_get_sink_info_list(lua_State* L)
+{
+    lua_pa_context* ctx = luaL_checkudata(L, 1, LUA_PA_CONTEXT);
+
+    if (pa_context_get_state(ctx->context) != PA_CONTEXT_READY) {
+        lua_pushvalue(L, 2);
+        lua_pushstring(L, "connection not ready");
+        lua_call(L, 1, 0);
+        return 0;
+    }
+
+    // Prepare a new thread to run the callback with
+    lua_pushstring(L, LUA_PULSEAUDIO);
+    lua_rawget(L, LUA_REGISTRYINDEX);
+    lua_pushstring(L, LUA_PA_REGISTRY);
+    lua_gettable(L, -2);
+    lua_State* thread = lua_newthread(L);
+    int thread_ref = luaL_ref(L, -2);
+
+    // Copy the callback function to the thread's stack
+    lua_pushvalue(L, 2);
+    lua_xmove(L, thread, 1);
+
+    // List to store the values in
+    lua_newtable(thread);
+
+    sink_info_list_callback_data* data = calloc(1, sizeof(struct sink_info_list_callback_data));
+    data->L = thread;
+    data->thread_ref = thread_ref;
+
+    pa_context_get_sink_info_list(ctx->context, sink_info_list_callback, data);
+    return 0;
+}
+
+
+typedef struct source_info_list_callback_data {
+    lua_State* L;
+    int thread_ref;
+} source_info_list_callback_data;
+
+
+void
+source_info_to_lua(lua_State* L, const pa_source_info* info)
+{
+    lua_createtable(L, 0, 24);
+    int table_index = lua_gettop(L);
+
+    lua_pushstring(L, "name");
+    lua_pushstring(L, info->name);
+    lua_settable(L, table_index);
+
+    // TODO: Handle rest of the table
+}
+
+
+void
+source_info_list_callback(pa_context* c, const pa_source_info* info, int eol, void* userdata)
+{
+    source_info_list_callback_data* data = (source_info_list_callback_data*) userdata;
+    lua_State* L = data->L;
+
+    if (eol == 0) {
+        int i = lua_objlen(L, 2);
+        lua_pushinteger(L, i+1);
+        source_info_to_lua(L, info);
+        lua_settable(L, 2);
+    } else {
+        // Insert the error argument
+        lua_pushnil(L);
+        lua_insert(L, -2);
+
+        lua_call(L, 2, 0);
+
+        lua_pushstring(L, LUA_PULSEAUDIO);
+        lua_rawget(L, LUA_REGISTRYINDEX);
+
+        lua_pushstring(L, LUA_PA_REGISTRY);
+        lua_gettable(L, -2);
+        luaL_unref(L, -1, data->thread_ref);
+        free(data);
+    }
+}
+
+
+int
+context_get_source_info_list(lua_State* L)
+{
+    lua_pa_context* ctx = luaL_checkudata(L, 1, LUA_PA_CONTEXT);
+
+    if (pa_context_get_state(ctx->context) != PA_CONTEXT_READY) {
+        lua_pushvalue(L, 2);
+        lua_pushstring(L, "connection not ready");
+        lua_call(L, 1, 0);
+        return 0;
+    }
+
+    // Prepare a new thread to run the callback with
+    lua_pushstring(L, LUA_PULSEAUDIO);
+    lua_rawget(L, LUA_REGISTRYINDEX);
+    lua_pushstring(L, LUA_PA_REGISTRY);
+    lua_gettable(L, -2);
+    lua_State* thread = lua_newthread(L);
+    int thread_ref = luaL_ref(L, -2);
+
+    // Copy the callback function to the thread's stack
+    lua_pushvalue(L, 2);
+    lua_xmove(L, thread, 1);
+
+    // List to store the values in
+    lua_newtable(thread);
+
+    source_info_list_callback_data* data = calloc(1, sizeof(struct source_info_list_callback_data));
+    data->L = thread;
+    data->thread_ref = thread_ref;
+
+    pa_context_get_source_info_list(ctx->context, source_info_list_callback, data);
+    return 0;
+}

src/lua_libpulse_glib/introspection.h

@@ -0,0 +1,10 @@
+#pragma once
+
+#include "lua.h"
+
+int
+context_get_server_info(lua_State*);
+int
+context_get_sink_info_list(lua_State*);
+int
+context_get_source_info_list(lua_State*);