#ifndef SUBPROCESS_H

#define SUBPROCESS_H

#include "hashmap.h"

#include "run-command.h"

/*

 * The sub-process API makes it possible to run background sub-processes

 * for the entire lifetime of a Git invocation. If Git needs to communicate

 * with an external process multiple times, then this can reduces the process

 * invocation overhead. Git and the sub-process communicate through stdin and

 * stdout.

 *

 * The sub-processes are kept in a hashmap by command name and looked up

 * via the subprocess_find_entry function.  If an existing instance can not

 * be found then a new process should be created and started.  When the

 * parent git command terminates, all sub-processes are also terminated.

 *

 * This API is based on the run-command API.

 */

 /* data structures */

/* Members should not be accessed directly. */

struct subprocess_entry {

  struct hashmap_entry ent;

  const char *cmd;

  struct child_process process;

};

struct subprocess_capability {

  const char *name;

  /*

   * subprocess_handshake will "|=" this value to supported_capabilities

   * if the server reports that it supports this capability.

   */

  unsigned int flag;

};

/* subprocess functions */

/* Function to test two subprocess hashmap entries for equality. */

int cmd2process_cmp(const void *unused_cmp_data,

        const struct hashmap_entry *e,

        const struct hashmap_entry *entry_or_key,

        const void *unused_keydata);

/*

 * User-supplied function to initialize the sub-process.  This is

 * typically used to negotiate the interface version and capabilities.

 */

typedef int(*subprocess_start_fn)(struct subprocess_entry *entry);

/* Start a subprocess and add it to the subprocess hashmap. */

int subprocess_start(struct hashmap *hashmap, struct subprocess_entry *entry, const char *cmd,

    subprocess_start_fn startfn);

/* Kill a subprocess and remove it from the subprocess hashmap. */

void subprocess_stop(struct hashmap *hashmap, struct subprocess_entry *entry);

/* Find a subprocess in the subprocess hashmap. */

struct subprocess_entry *subprocess_find_entry(struct hashmap *hashmap, const char *cmd);

/* subprocess helper functions */

/* Get the underlying `struct child_process` from a subprocess. */

static inline struct child_process *subprocess_get_child_process(

    struct subprocess_entry *entry)

{

  return &entry->process;

}

Unexecuted instantiation: convert.c:subprocess_get_child_process

Unexecuted instantiation: sub-process.c:subprocess_get_child_process

/*

 * Perform the version and capability negotiation as described in the

 * "Handshake" section of long-running-process-protocol.txt using the

 * given requested versions and capabilities. The "versions" and "capabilities"

 * parameters are arrays terminated by a 0 or blank struct.

 *

 * This function is typically called when a subprocess is started (as part of

 * the "startfn" passed to subprocess_start).

 */

int subprocess_handshake(struct subprocess_entry *entry,

       const char *welcome_prefix,

       int *versions,

       int *chosen_version,

       struct subprocess_capability *capabilities,

       unsigned int *supported_capabilities);

/*

 * Helper function that will read packets looking for "status=<foo>"

 * key/value pairs and return the value from the last "status" packet

 */

int subprocess_read_status(int fd, struct strbuf *status);

#endif