job: Refactor process spawning and startup arguments

- process spawning was decoupled from the rest of the job control logic.  The
  goal is reusing it for spawning processes connected to pseudo terminal file
  descriptors.
- job_start now receives a JobOptions structure containing all the startup
  options.

1 files changed, 37 insertions, 0 deletions

diff --git a/src/nvim/os/job_defs.h b/src/nvim/os/job_defs.h
index a9caa169a8..340ef551be 100644
--- a/src/nvim/os/job_defs.h
+++ b/src/nvim/os/job_defs.h
@@ -1,7 +1,9 @@
 #ifndef NVIM_OS_JOB_DEFS_H
 #define NVIM_OS_JOB_DEFS_H
 
+#include <uv.h>
 #include "nvim/os/rstream_defs.h"
+#include "nvim/os/wstream_defs.h"
 
 typedef struct job Job;
 
@@ -11,4 +13,39 @@ typedef struct job Job;
 /// @param data Some data associated with the job by the caller
 typedef void (*job_exit_cb)(Job *job, void *data);
 
+// Job startup options
+// job_exit_cb Callback that will be invoked when the job exits
+// maxmem Maximum amount of memory used by the job WStream
+typedef struct {
+  // Argument vector for the process. The first item is the
+  // executable to run.
+  // [consumed]
+  char **argv;
+  // Caller data that will be associated with the job
+  void *data;
+  // If true the job stdin will be available for writing with job_write,
+  // otherwise it will be redirected to /dev/null
+  bool writable;
+  // Callback that will be invoked when data is available on stdout. If NULL
+  // stdout will be redirected to /dev/null.
+  rstream_cb stdout_cb;
+  // Callback that will be invoked when data is available on stderr. If NULL
+  // stderr will be redirected to /dev/null.
+  rstream_cb  stderr_cb;
+  // Callback that will be invoked when the job has exited and will not send
+  // data
+  job_exit_cb exit_cb;
+  // Maximum memory used by the job's WStream
+  size_t maxmem;
+} JobOptions;
+
+#define JOB_OPTIONS_INIT ((JobOptions) {                     \
+    .argv = NULL,                                            \
+    .data = NULL,                                            \
+    .writable = true,                                        \
+    .stdout_cb = NULL,                                       \
+    .stderr_cb = NULL,                                       \
+    .exit_cb = NULL,                                         \
+    .maxmem = 0                                              \
+    })
 #endif  // NVIM_OS_JOB_DEFS_H