run-command.hon commit README: update stale and/or incorrect information (33b29fd)
   1#ifndef RUN_COMMAND_H
   2#define RUN_COMMAND_H
   3
   4#ifndef NO_PTHREADS
   5#include <pthread.h>
   6#endif
   7
   8struct child_process {
   9        const char **argv;
  10        pid_t pid;
  11        /*
  12         * Using .in, .out, .err:
  13         * - Specify 0 for no redirections (child inherits stdin, stdout,
  14         *   stderr from parent).
  15         * - Specify -1 to have a pipe allocated as follows:
  16         *     .in: returns the writable pipe end; parent writes to it,
  17         *          the readable pipe end becomes child's stdin
  18         *     .out, .err: returns the readable pipe end; parent reads from
  19         *          it, the writable pipe end becomes child's stdout/stderr
  20         *   The caller of start_command() must close the returned FDs
  21         *   after it has completed reading from/writing to it!
  22         * - Specify > 0 to set a channel to a particular FD as follows:
  23         *     .in: a readable FD, becomes child's stdin
  24         *     .out: a writable FD, becomes child's stdout/stderr
  25         *     .err: a writable FD, becomes child's stderr
  26         *   The specified FD is closed by start_command(), even in case
  27         *   of errors!
  28         */
  29        int in;
  30        int out;
  31        int err;
  32        const char *dir;
  33        const char *const *env;
  34        unsigned no_stdin:1;
  35        unsigned no_stdout:1;
  36        unsigned no_stderr:1;
  37        unsigned git_cmd:1; /* if this is to be git sub-command */
  38        unsigned silent_exec_failure:1;
  39        unsigned stdout_to_stderr:1;
  40        unsigned use_shell:1;
  41        unsigned clean_on_exit:1;
  42};
  43
  44int start_command(struct child_process *);
  45int finish_command(struct child_process *);
  46int run_command(struct child_process *);
  47
  48extern int run_hook(const char *index_file, const char *name, ...);
  49
  50#define RUN_COMMAND_NO_STDIN 1
  51#define RUN_GIT_CMD          2  /*If this is to be git sub-command */
  52#define RUN_COMMAND_STDOUT_TO_STDERR 4
  53#define RUN_SILENT_EXEC_FAILURE 8
  54#define RUN_USING_SHELL 16
  55#define RUN_CLEAN_ON_EXIT 32
  56int run_command_v_opt(const char **argv, int opt);
  57
  58/*
  59 * env (the environment) is to be formatted like environ: "VAR=VALUE".
  60 * To unset an environment variable use just "VAR".
  61 */
  62int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env);
  63
  64/*
  65 * The purpose of the following functions is to feed a pipe by running
  66 * a function asynchronously and providing output that the caller reads.
  67 *
  68 * It is expected that no synchronization and mutual exclusion between
  69 * the caller and the feed function is necessary so that the function
  70 * can run in a thread without interfering with the caller.
  71 */
  72struct async {
  73        /*
  74         * proc reads from in; closes it before return
  75         * proc writes to out; closes it before return
  76         * returns 0 on success, non-zero on failure
  77         */
  78        int (*proc)(int in, int out, void *data);
  79        void *data;
  80        int in;         /* caller writes here and closes it */
  81        int out;        /* caller reads from here and closes it */
  82#ifdef NO_PTHREADS
  83        pid_t pid;
  84#else
  85        pthread_t tid;
  86        int proc_in;
  87        int proc_out;
  88#endif
  89};
  90
  91int start_async(struct async *async);
  92int finish_async(struct async *async);
  93
  94#endif