very most basic functionality working

.gitignore

@@ -1,3 +1,4 @@
 .DS_Store
 cluepill
 *.o
+cluepill_conf.json

Makefile

@@ -1,8 +1,8 @@
 CC=clang
-CFLAGS=-c
+CFLAGS=-c -g
 LDFLAGS=
-SOURCES=main.c json.c args.c config.c util.c
-OBJECTS=$(SOURCES:.cpp=.o)
+SOURCES=main.c json.c args.c config.c util.c monitor.c
+OBJECTS=$(SOURCES:.c=.o)
 EXECUTABLE=cluepill
 
 all: $(SOURCES) $(EXECUTABLE)

cluepill_conf-sample.json

@@ -0,0 +1,18 @@
+{
+  "log": "/var/log/cluepill.log",
+  "processes": [
+    {
+      "name": "server",
+      "cd": "/Users/bjohnson/Desktop",
+      "exec": "node",
+      "args": [
+        "node",
+        "server.js"
+      ],
+      "start": true,
+      "pid_file": "/Users/bjohnson/Desktop/server.pid",
+      "stdout": "/Users/bjohnson/Desktop/server.stdout",
+      "stderr": "/Users/bjohnson/Desktop/server.stderr"
+    }
+  ]
+}

main.c

@@ -2,6 +2,7 @@
 
 #include "args.h"
 #include "config.h"
+#include "monitor.h"
 
 /*
  * main function
@@ -43,5 +44,7 @@ int main(int argc, char** argv) {
     p_config = p_config->next_process;
   }
 
+  monitor_processes(config);
+
   return 0;
 }

monitor.c

@@ -0,0 +1,76 @@
+#include "monitor.h"
+
+/*
+ *
+ */
+void monitor_processes(configuration *config) {
+  process_configuration *p_config;
+  pid_t check_pid;
+  int check_ret;
+
+  while(1) {
+    p_config = config->process_config;
+    while (p_config) {
+      char *pid_str = read_file(p_config->pid_file);
+      if (pid_str) {
+        check_pid = atoi(pid_str);
+        check_ret = kill(check_pid, 0);
+        if (check_ret != 0 && errno == ESRCH) {
+          printf("no such pid %d?\n", check_pid);
+          spawn_process(p_config);
+        }
+      } else {
+        // TODO
+        printf("no pid file %s?\n", p_config->pid_file);
+        spawn_process(p_config);
+      }
+      p_config = p_config->next_process;
+    }
+    sleep(1);
+    printf("*"); fflush(stdout);
+  }
+}
+
+/*
+ *
+ */
+int spawn_process(process_configuration *p_config) {
+
+  pid_t pid, pid2, sid;
+  int exec_ret;
+
+  pid = fork();
+  if (pid == -1) {
+    // fork failed
+    return -1;
+  } else if (pid == 0) {
+    // child process
+    umask(0); //unmask the file mode
+    sid = setsid(); // set new session
+    if(sid < 0) {
+      exit(1);
+    }
+    close(STDIN_FILENO); close(STDOUT_FILENO); close(STDERR_FILENO);
+    chdir("/");
+    pid2 = fork();
+    if (pid2 == -1) {
+      // fork failed
+      exit(1);
+    } else if (pid2 == 0) {
+      // child of child
+      chdir(p_config->cd);
+      exec_ret = execvp(p_config->exec, p_config->args);
+    } else {
+      // child
+      exit(0);
+    }
+    if (exec_ret != 0) {
+      exit(1);
+    }
+  } else {
+    // parent process
+    return 0;
+  }
+
+  return -1;
+}

monitor.h

@@ -0,0 +1,14 @@
+#ifndef __CLUEPILL_MONITOR
+#define __CLUEPILL_MONITOR
+
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+
+#include "config.h"
+#include "util.h"
+
+void monitor_processes(configuration *config);
+int spawn_process(process_configuration *p_config);
+
+#endif