From 88b724799aabd56fedd398e70c484c54960d0ae0 Mon Sep 17 00:00:00 2001
From: Jethro Grassie <jtg@xtrabass.com>
Date: Fri, 4 Sep 2020 01:48:57 -0400
Subject: [PATCH] initial multiprocess implementation

---
 pool.conf  |  1 +
 src/pool.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++------
 2 files changed, 56 insertions(+), 6 deletions(-)

diff --git a/pool.conf b/pool.conf
index 49498a5..990c5df 100644
--- a/pool.conf
+++ b/pool.conf
@@ -26,6 +26,7 @@ disable-payouts = 0
 data-dir = ./data
 pid-file =
 forked = 0
+processes = 1
 # trusted-listen = 127.0.0.1
 # trusted-port = 4244
 # trusted-allowed = 127.0.0.1,127.0.0.2
diff --git a/src/pool.c b/src/pool.c
index 8b570a0..c3eba16 100644
--- a/src/pool.c
+++ b/src/pool.c
@@ -34,6 +34,7 @@ developers.
 
 #include <netinet/in.h>
 #include <sys/socket.h>
+#include <sys/wait.h>
 #include <fcntl.h>
 
 #include <event2/event.h>
@@ -182,6 +183,7 @@ typedef struct config_t
     char upstream_host[MAX_HOST];
     uint16_t upstream_port;
     char pool_view_key[64];
+    int processes;
 } config_t;
 
 typedef struct block_template_t
@@ -3828,6 +3830,12 @@ read_config(const char *config_file)
         {
             config.forked = atoi(val);
         }
+        else if (strcmp(key, "processes") == 0)
+        {
+            config.processes = atoi(val);
+            if (config.processes < -1)
+                config.processes = -1;
+        }
         else if (strcmp(key, "trusted-listen") == 0)
         {
             strncpy(config.trusted_listen, val,
@@ -3966,6 +3974,7 @@ static void print_config()
         "  data-dir = %s\n"
         "  pid-file = %s\n"
         "  forked = %u\n"
+        "  processes = %d\n"
         "  trusted-listen = %s\n"
         "  trusted-port = %u\n"
         "  trusted-allowed = %s\n"
@@ -3999,6 +4008,7 @@ static void print_config()
         config.data_dir,
         config.pid_file,
         config.forked,
+        config.processes,
         config.trusted_listen,
         config.trusted_port,
         display_allowed,
@@ -4242,7 +4252,8 @@ print_help(struct option *opts)
     {
         printf("-%c, --%s %s\n", opts->val, opts->name,
             opts->has_arg==required_argument ?
-            strstr(opts->name,"file") ? "<file>" : "<dir>" :
+            strstr(opts->name,"file") ? "<file>" :
+            strstr(opts->name,"processes") ? "[-1|N]" : "<dir>" :
             opts->has_arg==optional_argument ? "[0|1]" : "" );
     }
 }
@@ -4257,6 +4268,7 @@ int main(int argc, char **argv)
         {"data-dir", required_argument, 0, 'd'},
         {"pid-file", required_argument, 0, 'p'},
         {"forked", optional_argument, 0, 'f'},
+        {"processes", required_argument, 0, 'm'},
         {"help", no_argument, 0, 'h'},
         {0, 0, 0, 0}
     };
@@ -4266,11 +4278,12 @@ int main(int argc, char **argv)
     char *data_dir = NULL;
     char *pid_file = NULL;
     int forked = -1;
+    int processes = 1;
     int c;
     while (1)
     {
         int option_index = 0;
-        c = getopt_long (argc, argv, "c:l:b::d:p:f::h",
+        c = getopt_long (argc, argv, "c:l:b::d:p:f::m:h",
                        options, &option_index);
         if (c == -1)
             break;
@@ -4306,6 +4319,11 @@ int main(int argc, char **argv)
                 else
                     forked = optarg ? atoi(optarg) : 1;
                 break;
+            case 'm':
+                processes = atoi(optarg);
+                if (processes < -1)
+                    processes = -1;
+                break;
             case 'h':
             default:
                 print_help(options);
@@ -4313,10 +4331,8 @@ int main(int argc, char **argv)
                 break;
         }
     }
-    setvbuf(stdout, NULL, _IONBF, 0);
+    setvbuf(stdout, NULL, _IOLBF, 0);
     log_set_level(LOG_INFO);
-    log_set_lock(log_lock);
-    log_set_udata(&mutex_log);
 
     read_config(config_file);
     if (config_file)
@@ -4340,6 +4356,8 @@ int main(int argc, char **argv)
     }
     if (forked > -1)
         config.forked = forked;
+    if (processes != 1)
+        config.processes = processes;
     if (block_notified > -1)
         config.block_notified = block_notified;
 
@@ -4350,7 +4368,10 @@ int main(int argc, char **argv)
         if (!fd_log)
             log_warn("Failed to open log file: %s", config.log_file);
         else
+        {
+            setvbuf(fd_log, NULL, _IOLBF, 0);
             log_set_fp(fd_log);
+        }
     }
 
     print_config();
@@ -4365,8 +4386,36 @@ int main(int argc, char **argv)
         forkoff(pf);
     }
 
-    int evthread_use_pthreads(void);
+    if (config.processes < 0 || config.processes > 1)
+    {
+        int nproc = sysconf(_SC_NPROCESSORS_ONLN);
+        if (config.processes > nproc)
+        {
+            log_warn("Requested more processes than available cores (%d)",
+                    nproc);
+            config.processes = -1;
+        }
+        nproc = config.processes < 0 ? nproc : config.processes;
+        log_info("Launching processes: %d", nproc);
+        int pid = 0;
+        while(nproc--)
+        {
+            pid = fork();
+            if (pid < 1)
+                break;
+            if (pid > 0)
+                continue;
+        }
+        if (pid > 0)
+        {
+            while (waitpid(-1, 0, 0) > 0)
+            {}
+            _exit(0);
+        }
+    }
 
+    log_set_udata(&mutex_log);
+    log_set_lock(log_lock);
     signal(SIGINT, sigint_handler);
     signal(SIGPIPE, SIG_IGN);
     atexit(cleanup);