Add log bindings for lua

1 files changed, 97 insertions, 0 deletions

diff --git a/src/lua/log.c b/src/lua/log.c
new file mode 100644
index 0000000..d02775c
--- /dev/null
+++ b/src/lua/log.c
@@ -0,0 +1,97 @@
+#include <assert.h>
+#include <string.h>
+
+#include "api.h"
+#include "../any_log.h"
+
+static int lua_log_format(lua_State *state, any_log_level_t level) {
+    const char *value = luaL_checkstring(state, 1);
+
+    lua_getglobal(state, "debug");
+    lua_getfield(state, -1, "getinfo");
+
+    // Ignore the first frame (lua_log_format itself)
+    lua_pushnumber(state, 2);
+    // S: source, l: currentline, n: name
+    lua_pushstring(state, "Sln");
+
+    const char *source = "x", *func = "y";
+    char buffer[4096] = { 0 };
+
+    if (lua_pcall(state, 2, 1, 0) == LUA_OK) {
+
+        lua_getfield(state, -1, "short_src");
+        const char *shortsrc = lua_tostring(state, -1);
+
+        lua_getfield(state, -2, "currentline");
+        int line = lua_tointeger(state, -1);
+
+        if (!strncmp(shortsrc, "[string ", 8)) {
+            int length = strlen(shortsrc);
+            snprintf(buffer, sizeof(buffer), "lua %.*s", length - 9, shortsrc + 8);
+        } else {
+            snprintf(buffer, sizeof(buffer), "lua %s:%d", shortsrc, line);
+        }
+
+        source = buffer;
+
+        lua_getfield(state, -3, "name");
+        const char *name = lua_tostring(state, -1);
+
+        func = name == NULL
+             ? "..."
+             : name;
+    }
+
+    lua_pop(state, 3);
+    any_log_format(level, source, func, "%s", value);
+    return 0;
+}
+
+static int lua_log_log(lua_State *state) {
+    const char *level = luaL_checkstring(state, 1);
+    lua_pop(state, 1);
+    any_log_level_t l = any_log_level_from_string(level);
+    assert(l > ANY_LOG_ALL);
+    return lua_log_format(state, l);
+}
+
+static int lua_log_panic(lua_State *state) {
+    return lua_log_format(state, ANY_LOG_PANIC);
+}
+
+static int lua_log_error(lua_State *state) {
+    return lua_log_format(state, ANY_LOG_ERROR);
+}
+
+static int lua_log_warn(lua_State *state) {
+    return lua_log_format(state, ANY_LOG_WARN);
+}
+
+static int lua_log_info(lua_State *state) {
+    return lua_log_format(state, ANY_LOG_INFO);
+}
+
+static int lua_log_debug(lua_State *state) {
+    return lua_log_format(state, ANY_LOG_DEBUG);
+}
+
+static int lua_log_trace(lua_State *state) {
+    return lua_log_format(state, ANY_LOG_TRACE);
+}
+
+int lua_log_library(lua_State *state)
+{
+    static const luaL_Reg library[] = {
+        { "log",   lua_log_log },
+        { "panic", lua_log_panic },
+        { "error", lua_log_error },
+        { "warn",  lua_log_warn },
+        { "info",  lua_log_info },
+        { "debug", lua_log_debug },
+        { "trace", lua_log_trace },
+        { NULL, NULL },
+    };
+    luaL_newlib(state, library);
+    return 1;
+}