run-command.h

   1 #ifndef RUN_COMMAND_H
   2 #define RUN_COMMAND_H
   3
   4 #ifndef NO_PTHREADS
   5 #include <pthread.h>
   6 #endif
   7
   8 struct 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         void (*preexec_cb)(void);
  42 };
  43
  44 int start_command(struct child_process *);
  45 int finish_command(struct child_process *);
  46 int run_command(struct child_process *);
  47
  48 extern 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 int run_command_v_opt(const char **argv, int opt);
  56
  57 /*
  58  * env (the environment) is to be formatted like environ: "VAR=VALUE".
  59  * To unset an environment variable use just "VAR".
  60  */
  61 int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env);
  62
  63 /*
  64  * The purpose of the following functions is to feed a pipe by running
  65  * a function asynchronously and providing output that the caller reads.
  66  *
  67  * It is expected that no synchronization and mutual exclusion between
  68  * the caller and the feed function is necessary so that the function
  69  * can run in a thread without interfering with the caller.
  70  */
  71 struct async {
  72         /*
  73          * proc reads from in; closes it before return
  74          * proc writes to out; closes it before return
  75          * returns 0 on success, non-zero on failure
  76          */
  77         int (*proc)(int in, int out, void *data);
  78         void *data;
  79         int in;         /* caller writes here and closes it */
  80         int out;        /* caller reads from here and closes it */
  81 #ifdef NO_PTHREADS
  82         pid_t pid;
  83 #else
  84         pthread_t tid;
  85         int proc_in;
  86         int proc_out;
  87 #endif
  88 };
  89
  90 int start_async(struct async *async);
  91 int finish_async(struct async *async);
  92
  93 #endif