5 files changed, 348 insertions, 3 deletions

diff --git a/source/kit/_lib.c b/source/kit/_lib.c
index 3b5d97a..0f7cc19 100644
--- a/source/kit/_lib.c
+++ b/source/kit/_lib.c
@@ -10,6 +10,8 @@
 #include "atomic.win32.c"
 #include "threads.posix.c"
 #include "threads.win32.c"
+#include "process.posix.c"
+#include "process.win32.c"
 #include "shared_memory.posix.c"
 #include "shared_memory.win32.c"
 #include "xml.c"
diff --git a/source/kit/process.h b/source/kit/process.h
index 4a56055..f0aa200 100644
--- a/source/kit/process.h
+++ b/source/kit/process.h
@@ -7,14 +7,31 @@
 #include "types.h"
 #include "string_ref.h"
 
+#if !defined(_WIN32) || defined(__CYGWIN__)
+#  include <unistd.h>
+#else
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
 
+enum {
+  KIT_PROCESS_NO_ARGUMENTS   = 1,
+  KIT_PROCESS_NO_ENVIRONMENT = (1 << 1),
+  KIT_PROCESS_NO_PIPES       = (1 << 2),
+};
+
 typedef struct {
   s32 status;
-  i32 exit_code;
-#if defined(_WIN32) && !defined(__CYGWIN__)
+  u8  exit_code;
+#if !defined(_WIN32) || defined(__CYGWIN__)
+  b8    _ready;
+  b8    _running;
+  pid_t _id;
+  i32   _stdin;
+  i32   _stdout;
+  i32   _stderr;
 #else
 #endif
 } kit_process_t;
@@ -28,18 +45,21 @@ typedef KIT_AR(kit_str_t) kit_process_args_t;
 typedef KIT_AR(kit_process_env_var_t) kit_process_env_t;
 
 typedef struct {
+  u32                flags;
   kit_str_t          file_name;
   kit_process_args_t command_line;
   kit_process_env_t  environment;
   kit_str_t          working_directory;
 } kit_process_info_t;
 
-s32 kit_process_init(kit_process_t *p, kit_process_info_t info);
+s32  kit_process_init(kit_process_t *p, kit_process_info_t info);
+void kit_process_cleanup(kit_process_t *p);
 
 i64 kit_process_write_stdin(kit_process_t *p, kit_str_t in_data);
 i64 kit_process_read_stdout(kit_process_t *p, kit_str_t out_data);
 i64 kit_process_read_stderr(kit_process_t *p, kit_str_t out_data);
 s32 kit_process_terminate(kit_process_t *p);
+b8  kit_process_alive(kit_process_t *p);
 s32 kit_process_wait(kit_process_t *p);
 
 #ifdef __cplusplus
diff --git a/source/kit/process.posix.c b/source/kit/process.posix.c
index aaf2a9f..b4039e6 100644
--- a/source/kit/process.posix.c
+++ b/source/kit/process.posix.c
@@ -1 +1,309 @@
 #include "process.h"
+
+#if !defined(_WIN32) || defined(__CYGWIN__)
+#  include "status.h"
+
+#  include <assert.h>
+#  include <fcntl.h>
+#  include <signal.h>
+#  include <sys/wait.h>
+
+char *kit_process_argv_null_[] = { "", NULL };
+char *kit_process_env_null_[]  = { NULL };
+
+char **kit_init_argv_(kit_process_args_t args, u32 flags) {
+  //  TODO
+  //
+
+  if ((flags & KIT_PROCESS_NO_ARGUMENTS) != 0)
+    return kit_process_argv_null_;
+
+  return NULL;
+}
+
+char **kit_init_envp_(kit_process_env_t env, u32 flags) {
+  //  TODO
+  //
+
+  if ((flags & KIT_PROCESS_NO_ENVIRONMENT) != 0)
+    return kit_process_env_null_;
+
+  return NULL;
+}
+
+s32 kit_process_init(kit_process_t *p, kit_process_info_t info) {
+  assert(p != NULL);
+  assert(info.working_directory.size == 0 ||
+         info.working_directory.values != NULL);
+
+  if (p == NULL || (info.working_directory.size != 0 &&
+                    info.working_directory.values == NULL))
+    return KIT_ERROR_INVALID_ARGUMENT;
+
+  memset(p, 0, sizeof *p);
+
+  p->_stdin  = -1;
+  p->_stdout = -1;
+  p->_stderr = -1;
+
+  signal(SIGCHLD, SIG_IGN);
+  signal(SIGALRM, SIG_IGN); // pipes
+
+  i32 pipe_in[2];
+  i32 pipe_out[2];
+  i32 pipe_err[2];
+
+  if ((info.flags & KIT_PROCESS_NO_PIPES) == 0) {
+    if (pipe(pipe_in) == -1) {
+      assert(0);
+      return KIT_ERROR_PIPE_FAILED;
+    }
+
+    if (pipe(pipe_out) == -1) {
+      assert(0);
+      close(pipe_in[0]);
+      close(pipe_in[1]);
+      return KIT_ERROR_PIPE_FAILED;
+    }
+
+    if (pipe(pipe_err) == -1) {
+      assert(0);
+      close(pipe_in[0]);
+      close(pipe_in[1]);
+      close(pipe_out[0]);
+      close(pipe_out[1]);
+      return KIT_ERROR_PIPE_FAILED;
+    }
+
+    //  non-blocking writing for stdout, stderr
+    if (fcntl(pipe_out[1], F_SETFL, O_NONBLOCK) == -1 ||
+        fcntl(pipe_err[1], F_SETFL, O_NONBLOCK) == -1) {
+      assert(0);
+      close(pipe_in[0]);
+      close(pipe_in[1]);
+      close(pipe_out[0]);
+      close(pipe_out[1]);
+      close(pipe_err[0]);
+      close(pipe_err[1]);
+      return KIT_ERROR_PIPE_FAILED;
+    }
+  }
+
+  pid_t id = fork();
+
+  //  NOTE
+  //  We can safely use BS because there's only one thread after
+  //  fork.
+  //
+
+  switch (id) {
+    case -1: return KIT_ERROR_FORK_FAILED;
+
+    case 0:
+      //  Child process
+      //
+
+      if ((info.flags & KIT_PROCESS_NO_PIPES) == 0) {
+        //  Redirect IO
+        if (dup2(pipe_in[0], STDIN_FILENO) == -1 ||
+            dup2(pipe_out[1], STDOUT_FILENO) == -1 ||
+            dup2(pipe_err[1], STDERR_FILENO) == -1) {
+          assert(0);
+          close(pipe_in[0]);
+          close(pipe_in[1]);
+          close(pipe_out[0]);
+          close(pipe_out[1]);
+          close(pipe_err[0]);
+          close(pipe_err[1]);
+          return KIT_ERROR_DUP2_FAILED;
+        }
+
+        //  Close pipes
+        close(pipe_in[0]);
+        close(pipe_in[1]);
+        close(pipe_out[0]);
+        close(pipe_out[1]);
+        close(pipe_err[0]);
+        close(pipe_err[1]);
+      }
+
+      //  Change working directory
+      if (info.working_directory.size != 0 &&
+          chdir(BS(info.working_directory)) == -1) {
+        assert(0);
+        return KIT_ERROR_CHDIR_FAILED;
+      }
+
+      execve(BS(info.file_name),
+             kit_init_argv_(info.command_line, info.flags),
+             kit_init_envp_(info.environment, info.flags));
+      // Doesn't return on success
+
+      return KIT_ERROR_EXECVE_FAILED;
+
+    default:
+      //  Parent process
+      //
+
+      p->status   = KIT_OK;
+      p->_ready   = 1;
+      p->_running = 1;
+      p->_id      = id;
+
+      if ((info.flags & KIT_PROCESS_NO_PIPES) == 0) {
+        p->_stdin  = pipe_in[1];
+        p->_stdout = pipe_out[0];
+        p->_stderr = pipe_err[0];
+
+        //  Close unused pipes
+        close(pipe_in[0]);
+        close(pipe_out[1]);
+        close(pipe_err[1]);
+      }
+  }
+
+  return KIT_OK;
+}
+
+void kit_process_cleanup(kit_process_t *p) {
+  assert(p != NULL);
+  assert(p->_ready);
+
+  if (p == NULL || !p->_ready)
+    return;
+
+  if (p->_stdin != -1)
+    close(p->_stdin);
+  if (p->_stdout != -1)
+    close(p->_stdout);
+  if (p->_stderr != -1)
+    close(p->_stderr);
+
+  memset(p, 0, sizeof *p);
+}
+
+i64 kit_process_write_stdin(kit_process_t *p, kit_str_t in_data) {
+  assert(p != NULL && (in_data.size == 0 || in_data.values != NULL) &&
+         p->_running);
+
+  if (p == NULL || (in_data.size != 0 && in_data.values == NULL))
+    return KIT_ERROR_INVALID_ARGUMENT;
+  if (in_data.size == 0 || !p->_running || p->_stdin == -1)
+    return 0;
+
+  i64 n = write(p->_stdin, in_data.values, in_data.size);
+
+  assert(n >= 0);
+  if (n < 0)
+    return 0;
+
+  return n;
+}
+
+i64 kit_process_read_stdout(kit_process_t *p, kit_str_t out_data) {
+  assert(p != NULL &&
+         (out_data.size == 0 || out_data.values != NULL) &&
+         p->_ready);
+
+  if (p == NULL || (out_data.size != 0 && out_data.values == NULL))
+    return KIT_ERROR_INVALID_ARGUMENT;
+  if (out_data.size == 0 || !p->_ready || p->_stdout == -1)
+    return 0;
+
+  i64 n = read(p->_stdout, out_data.values, out_data.size);
+
+  assert(n >= 0);
+  if (n < 0)
+    return 0;
+
+  return n;
+}
+
+i64 kit_process_read_stderr(kit_process_t *p, kit_str_t out_data) {
+  assert(p != NULL &&
+         (out_data.size == 0 || out_data.values != NULL) &&
+         p->_ready);
+
+  if (p == NULL || (out_data.size != 0 && out_data.values == NULL))
+    return KIT_ERROR_INVALID_ARGUMENT;
+  if (out_data.size == 0 || !p->_ready || p->_stderr == -1)
+    return 0;
+
+  i64 n = read(p->_stderr, out_data.values, out_data.size);
+
+  assert(n >= 0);
+  if (n < 0)
+    return 0;
+
+  return n;
+}
+
+s32 kit_process_terminate(kit_process_t *p) {
+  assert(p != NULL && p->_running);
+  if (p == NULL || !p->_running)
+    return KIT_ERROR_INVALID_ARGUMENT;
+
+  if (kill(p->_id, SIGTERM) == -1)
+    return KIT_ERROR_KILL_FAILED;
+
+  return KIT_OK;
+}
+
+b8 kit_process_alive(kit_process_t *p) {
+  assert(p != NULL);
+  if (p == NULL || p->status != KIT_OK)
+    return 0;
+
+  if (!p->_running)
+    return 0;
+
+  int status;
+
+  pid_t id = waitpid(p->_id, &status, WNOHANG);
+
+  if (id == -1) {
+    p->status = KIT_ERROR_WAITPID_FAILED;
+    return 0;
+  }
+
+  if (id == 0)
+    return 1;
+
+  if (WIFEXITED(status)) {
+    p->exit_code = WEXITSTATUS(status);
+    p->_running  = 0;
+    return 0;
+  }
+
+  return 1;
+}
+
+s32 kit_process_wait(kit_process_t *p) {
+  assert(p != NULL);
+  if (p == NULL)
+    return KIT_ERROR_INVALID_ARGUMENT;
+
+  if (p->status != KIT_OK)
+    return p->status;
+  if (!p->_running)
+    return KIT_OK;
+
+  for (;;) {
+    int status;
+
+    pid_t id = waitpid(p->_id, &status, 0);
+
+    if (id == -1)
+      return KIT_ERROR_WAITPID_FAILED;
+
+    if (WIFEXITED(status)) {
+      p->exit_code = WEXITSTATUS(status);
+      p->_running  = 0;
+      break;
+    }
+  }
+
+  return KIT_OK;
+}
+
+#endif
diff --git a/source/kit/process.win32.c b/source/kit/process.win32.c
index aaf2a9f..ebff7b1 100644
--- a/source/kit/process.win32.c
+++ b/source/kit/process.win32.c
@@ -1 +1,5 @@
 #include "process.h"
+
+#if defined(_WIN32) && !defined(__CYGWIN__)
+
+#endif
diff --git a/source/kit/status.h b/source/kit/status.h
index 9d1eb70..7ea1c4d 100644
--- a/source/kit/status.h
+++ b/source/kit/status.h
@@ -1,6 +1,10 @@
 #ifndef KIT_STATUS_H
 #define KIT_STATUS_H
 
+#ifndef _GNU_SOURCE
+#  define _GNU_SOURCE
+#endif
+
 enum {
   KIT_OK                           = 0,
   KIT_PARSING_FAILED               = 1,
@@ -25,6 +29,13 @@ enum {
   KIT_ERROR_SYNC_FAILED            = (1 << 19),
   KIT_ERROR_CLOSE_FAILED           = (1 << 20),
   KIT_ERROR_RESOURCE_UNAVAILABLE   = (1 << 21),
+  KIT_ERROR_FORK_FAILED            = (1 << 22),
+  KIT_ERROR_EXECVE_FAILED          = (1 << 23),
+  KIT_ERROR_WAITPID_FAILED         = (1 << 24),
+  KIT_ERROR_PIPE_FAILED            = (1 << 25),
+  KIT_ERROR_DUP2_FAILED            = (1 << 26),
+  KIT_ERROR_CHDIR_FAILED           = (1 << 27),
+  KIT_ERROR_KILL_FAILED            = (1 << 28),
   KIT_ERROR_INTERNAL               = (1 << 30),
   KIT_ERROR_NOT_IMPLEMENTED        = -1,
 };