Lua function creation on EVAL, basic Lua return type to Redis protocol convertion done.

src/Makefile

@@ -39,7 +39,6 @@ PREFIX= /usr/local
 INSTALL_BIN= $(PREFIX)/bin
 INSTALL= cp -p
 
-
 CCCOLOR="\033[34m"
 LINKCOLOR="\033[34;1m"
 SRCCOLOR="\033[33m"
@@ -47,7 +46,7 @@ BINCOLOR="\033[37;1m"
 MAKECOLOR="\033[32;1m"
 ENDCOLOR="\033[0m"
 
-OBJ = adlist.o ae.o anet.o dict.o redis.o sds.o zmalloc.o lzf_c.o lzf_d.o pqsort.o zipmap.o sha1.o ziplist.o release.o networking.o util.o object.o db.o replication.o rdb.o t_string.o t_list.o t_set.o t_zset.o t_hash.o config.o aof.o dscache.o pubsub.o multi.o debug.o sort.o intset.o syncio.o diskstore.o cluster.o crc16.o endian.o
+OBJ = adlist.o ae.o anet.o dict.o redis.o sds.o zmalloc.o lzf_c.o lzf_d.o pqsort.o zipmap.o sha1.o ziplist.o release.o networking.o util.o object.o db.o replication.o rdb.o t_string.o t_list.o t_set.o t_zset.o t_hash.o config.o aof.o dscache.o pubsub.o multi.o debug.o sort.o intset.o syncio.o diskstore.o cluster.o crc16.o endian.o scripting.o
 BENCHOBJ = ae.o anet.o redis-benchmark.o sds.o adlist.o zmalloc.o
 CLIOBJ = anet.o sds.o adlist.o redis-cli.o zmalloc.o release.o
 CHECKDUMPOBJ = redis-check-dump.o lzf_c.o lzf_d.o

src/redis.c

@@ -193,7 +193,8 @@ struct redisCommand redisCommandTable[] = {
     {"migrate",migrateCommand,6,0,NULL,0,0,0,0,0},
     {"dump",dumpCommand,2,0,NULL,0,0,0,0,0},
     {"object",objectCommand,-2,0,NULL,0,0,0,0,0},
-    {"client",clientCommand,-2,0,NULL,0,0,0,0,0}
+    {"client",clientCommand,-2,0,NULL,0,0,0,0,0},
+    {"eval",evalCommand,-3,0,NULL,0,0,0,0,0}
 };
 
 /*============================ Utility functions ============================ */
@@ -981,6 +982,7 @@ void initServer() {
 
     if (server.ds_enabled) dsInit();
     if (server.cluster_enabled) clusterInit();
+    scriptingInit();
     srand(time(NULL)^getpid());
 }
 

src/redis.h

@@ -19,6 +19,7 @@
 #include <pthread.h>
 #include <syslog.h>
 #include <netinet/in.h>
+#include <lua.h>
 
 #include "ae.h"     /* Event driven programming library */
 #include "sds.h"    /* Dynamic safe strings */
@@ -654,6 +655,8 @@ struct redisServer {
     /* Cluster */
     int cluster_enabled;
     clusterState cluster;
+    /* Scripting */
+    lua_State *lua;
 };
 
 typedef struct pubsubPattern {
@@ -1075,6 +1078,9 @@ int clusterAddNode(clusterNode *node);
 void clusterCron(void);
 clusterNode *getNodeByQuery(redisClient *c, struct redisCommand *cmd, robj **argv, int argc, int *hashslot, int *ask);
 
+/* Scripting */
+void scriptingInit(void);
+
 /* Git SHA1 */
 char *redisGitSHA1(void);
 char *redisGitDirty(void);
@@ -1203,6 +1209,7 @@ void migrateCommand(redisClient *c);
 void dumpCommand(redisClient *c);
 void objectCommand(redisClient *c);
 void clientCommand(redisClient *c);
+void evalCommand(redisClient *c);
 
 #if defined(__GNUC__)
 void *calloc(size_t count, size_t size) __attribute__ ((deprecated));

src/scripting.c

@@ -0,0 +1,100 @@
+#include "redis.h"
+#include "sha1.h"
+
+#include <lua.h>
+#include <lauxlib.h>
+#include <lualib.h>
+
+void scriptingInit(void) {
+    lua_State *lua = lua_open();
+    luaL_openlibs(lua);
+    server.lua = lua;
+}
+
+/* Hash the scripit into a SHA1 digest. We use this as Lua function name.
+ * Digest should point to a 41 bytes buffer: 40 for SHA1 converted into an
+ * hexadecimal number, plus 1 byte for null term. */
+void hashScript(char *digest, char *script, size_t len) {
+    SHA1_CTX ctx;
+    unsigned char hash[20];
+    char *cset = "0123456789abcdef";
+    int j;
+
+    SHA1Init(&ctx);
+    SHA1Update(&ctx,(unsigned char*)script,len);
+    SHA1Final(hash,&ctx);
+
+    for (j = 0; j < 20; j++) {
+        digest[j*2] = cset[((hash[j]&0xF0)>>4)];
+        digest[j*2+1] = cset[(hash[j]&0xF)];
+    }
+    digest[40] = '\0';
+}
+
+void luaReplyToRedisReply(redisClient *c, lua_State *lua) {
+    int t = lua_type(lua,1);
+
+    switch(t) {
+    case LUA_TSTRING:
+        addReplyBulkCBuffer(c,(char*)lua_tostring(lua,1),lua_strlen(lua,1));
+        break;
+    case LUA_TBOOLEAN:
+        addReply(c,lua_toboolean(lua,1) ? shared.cone : shared.czero);
+        break;
+    case LUA_TNUMBER:
+        addReplyLongLong(c,(long long)lua_tonumber(lua,1));
+        break;
+    default:
+        addReply(c,shared.nullbulk);
+    }
+    lua_pop(lua,1);
+}
+
+void evalCommand(redisClient *c) {
+    lua_State *lua = server.lua;
+    char funcname[43];
+
+    /* We obtain the script SHA1, then check if this function is already
+     * defined into the Lua state */
+    funcname[0] = 'f';
+    funcname[1] = '_';
+    hashScript(funcname+2,c->argv[1]->ptr,sdslen(c->argv[1]->ptr));
+    lua_getglobal(lua, funcname);
+    if (lua_isnil(lua,1)) {
+        /* Function not defined... let's define it. */
+        sds funcdef = sdsempty();
+
+        lua_pop(lua,1); /* remove the nil from the stack */
+        funcdef = sdscat(funcdef,"function ");
+        funcdef = sdscatlen(funcdef,funcname,42);
+        funcdef = sdscatlen(funcdef," ()\n",4);
+        funcdef = sdscatlen(funcdef,c->argv[1]->ptr,sdslen(c->argv[1]->ptr));
+        funcdef = sdscatlen(funcdef,"\nend\n",5);
+        printf("Defining:\n%s\n",funcdef);
+
+        if (luaL_loadbuffer(lua,funcdef,sdslen(funcdef),"func definition")) {
+            addReplyErrorFormat(c,"Error compiling script (new function): %s\n",
+                lua_tostring(lua,-1));
+            lua_pop(lua,1);
+            return;
+        }
+        if (lua_pcall(lua,0,0,0)) {
+            addReplyErrorFormat(c,"Error running script (new function): %s\n",
+                lua_tostring(lua,-1));
+            lua_pop(lua,1);
+            return;
+        }
+        lua_getglobal(lua, funcname);
+    }
+    
+    /* At this point whatever this script was never seen before or if it was
+     * already defined, we can call it. We have zero arguments and expect
+     * a single return value. */
+    if (lua_pcall(lua,0,1,0)) {
+        addReplyErrorFormat(c,"Error running script (call to %s): %s\n",
+            funcname, lua_tostring(lua,-1));
+        lua_pop(lua,1);
+        return;
+    }
+    luaReplyToRedisReply(c,lua);
+}