From 58573f1dd2d6d3cfd5dbaea7484c55571f856b3b Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Tue, 17 Nov 2015 12:11:13 +0100
Subject: [PATCH] Lua debugger: redis-cli can restart Lua debugging sessions.

---
 src/redis-cli.c | 120 ++++++++++++++++++++++++++++++------------------
 1 file changed, 75 insertions(+), 45 deletions(-)

diff --git a/src/redis-cli.c b/src/redis-cli.c
index 80391074..a5836b29 100644
--- a/src/redis-cli.c
+++ b/src/redis-cli.c
@@ -1106,6 +1106,12 @@ static void repl(void) {
                     strcasecmp(argv[0],"exit") == 0)
                 {
                     exit(0);
+                } else if (strcasecmp(argv[0],"restart") == 0) {
+                    if (config.eval_ldb) {
+                        return; /* Return to evalMode to restart the session. */
+                    } else {
+                        printf("Use 'restart' only in Lua debugging mode.");
+                    }
                 } else if (argc == 3 && !strcasecmp(argv[0],"connect")) {
                     sdsfree(config.hostip);
                     config.hostip = sdsnew(argv[1]);
@@ -1169,59 +1175,83 @@ static int noninteractive(int argc, char **argv) {
  *--------------------------------------------------------------------------- */
 
 static int evalMode(int argc, char **argv) {
-    sds script = sdsempty();
+    sds script = NULL;
     FILE *fp;
     char buf[1024];
     size_t nread;
     char **argv2;
-    int j, got_comma = 0, keys = 0;
+    int j, got_comma, keys;
+    int retval = REDIS_OK;
 
-    /* Load the script from the file, as an sds string. */
-    fp = fopen(config.eval,"r");
-    if (!fp) {
-        fprintf(stderr,
-            "Can't open file '%s': %s\n", config.eval, strerror(errno));
-        exit(1);
-    }
-    while((nread = fread(buf,1,sizeof(buf),fp)) != 0) {
-        script = sdscatlen(script,buf,nread);
-    }
-    fclose(fp);
-
-    /* If we are debugging a script, enable the Lua debugger. */
-    if (config.eval_ldb) {
-        redisReply *reply = redisCommand(context,
-                config.eval_ldb_sync ? "SCRIPT DEBUG sync": "SCRIPT DEBUG yes");
-        if (reply) freeReplyObject(reply);
-    }
-
-    /* Create our argument vector */
-    argv2 = zmalloc(sizeof(sds)*(argc+3));
-    argv2[0] = sdsnew("EVAL");
-    argv2[1] = script;
-    for (j = 0; j < argc; j++) {
-        if (!got_comma && argv[j][0] == ',' && argv[j][1] == 0) {
-            got_comma = 1;
-            continue;
+    while(1) {
+        if (config.eval_ldb) {
+            printf(
+            "Lua debugging session started, please use:\n"
+            "quit    -- End the session.\n"
+            "restart -- Restart the script in debug mode again.\n"
+            "help    -- Show Lua script debugging commands.\n\n"
+            );
         }
-        argv2[j+3-got_comma] = sdsnew(argv[j]);
-        if (!got_comma) keys++;
-    }
-    argv2[2] = sdscatprintf(sdsempty(),"%d",keys);
 
-    /* Call it */
-    int eval_ldb = config.eval_ldb; /* Save it, may be reverteed. */
-    int retval = issueCommand(argc+3-got_comma, argv2);
-    if (eval_ldb) {
-        if (!config.eval_ldb) {
-            /* If the debugging session ended immediately, there was an
-             * error compiling the script. Show it and don't enter
-             * the REPL at all. */
-            printf("Eval debugging session can't start:\n");
-            cliReadReply(0);
+        sdsfree(script);
+        script = sdsempty();
+        got_comma = 0;
+        keys = 0;
+
+        /* Load the script from the file, as an sds string. */
+        fp = fopen(config.eval,"r");
+        if (!fp) {
+            fprintf(stderr,
+                "Can't open file '%s': %s\n", config.eval, strerror(errno));
+            exit(1);
+        }
+        while((nread = fread(buf,1,sizeof(buf),fp)) != 0) {
+            script = sdscatlen(script,buf,nread);
+        }
+        fclose(fp);
+
+        /* If we are debugging a script, enable the Lua debugger. */
+        if (config.eval_ldb) {
+            redisReply *reply = redisCommand(context,
+                    config.eval_ldb_sync ?
+                    "SCRIPT DEBUG sync": "SCRIPT DEBUG yes");
+            if (reply) freeReplyObject(reply);
+        }
+
+        /* Create our argument vector */
+        argv2 = zmalloc(sizeof(sds)*(argc+3));
+        argv2[0] = sdsnew("EVAL");
+        argv2[1] = script;
+        for (j = 0; j < argc; j++) {
+            if (!got_comma && argv[j][0] == ',' && argv[j][1] == 0) {
+                got_comma = 1;
+                continue;
+            }
+            argv2[j+3-got_comma] = sdsnew(argv[j]);
+            if (!got_comma) keys++;
+        }
+        argv2[2] = sdscatprintf(sdsempty(),"%d",keys);
+
+        /* Call it */
+        int eval_ldb = config.eval_ldb; /* Save it, may be reverteed. */
+        retval = issueCommand(argc+3-got_comma, argv2);
+        if (eval_ldb) {
+            if (!config.eval_ldb) {
+                /* If the debugging session ended immediately, there was an
+                 * error compiling the script. Show it and don't enter
+                 * the REPL at all. */
+                printf("Eval debugging session can't start:\n");
+                cliReadReply(0);
+                break; /* Return to the caller. */
+            } else {
+                strncpy(config.prompt,"lua debugger> ",sizeof(config.prompt));
+                repl();
+                /* Restart the session if repl() returned. */
+                cliConnect(1);
+                printf("\n");
+            }
         } else {
-            strncpy(config.prompt,"lua debugger> ",sizeof(config.prompt));
-            repl();
+            break; /* Return to the caller. */
         }
     }
     return retval;