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 #include "argv-array.h"
   9
  10 struct child_process {
  11         const char **argv;
  12         struct argv_array args;
  13         struct argv_array env_array;
  14         pid_t pid;
  15         /*
  16          * Using .in, .out, .err:
  17          * - Specify 0 for no redirections (child inherits stdin, stdout,
  18          *   stderr from parent).
  19          * - Specify -1 to have a pipe allocated as follows:
  20          *     .in: returns the writable pipe end; parent writes to it,
  21          *          the readable pipe end becomes child's stdin
  22          *     .out, .err: returns the readable pipe end; parent reads from
  23          *          it, the writable pipe end becomes child's stdout/stderr
  24          *   The caller of start_command() must close the returned FDs
  25          *   after it has completed reading from/writing to it!
  26          * - Specify > 0 to set a channel to a particular FD as follows:
  27          *     .in: a readable FD, becomes child's stdin
  28          *     .out: a writable FD, becomes child's stdout/stderr
  29          *     .err: a writable FD, becomes child's stderr
  30          *   The specified FD is closed by start_command(), even in case
  31          *   of errors!
  32          */
  33         int in;
  34         int out;
  35         int err;
  36         const char *dir;
  37         const char *const *env;
  38         unsigned no_stdin:1;
  39         unsigned no_stdout:1;
  40         unsigned no_stderr:1;
  41         unsigned git_cmd:1; /* if this is to be git sub-command */
  42         unsigned silent_exec_failure:1;
  43         unsigned stdout_to_stderr:1;
  44         unsigned use_shell:1;
  45         unsigned clean_on_exit:1;
  46 };
  47
  48 #define CHILD_PROCESS_INIT { NULL, ARGV_ARRAY_INIT, ARGV_ARRAY_INIT }
  49 void child_process_init(struct child_process *);
  50
  51 int start_command(struct child_process *);
  52 int finish_command(struct child_process *);
  53 int run_command(struct child_process *);
  54
  55 /*
  56  * Returns the path to the hook file, or NULL if the hook is missing
  57  * or disabled. Note that this points to static storage that will be
  58  * overwritten by further calls to find_hook and run_hook_*.
  59  */
  60 extern const char *find_hook(const char *name);
  61 LAST_ARG_MUST_BE_NULL
  62 extern int run_hook_le(const char *const *env, const char *name, ...);
  63 extern int run_hook_ve(const char *const *env, const char *name, va_list args);
  64
  65 #define RUN_COMMAND_NO_STDIN 1
  66 #define RUN_GIT_CMD          2  /*If this is to be git sub-command */
  67 #define RUN_COMMAND_STDOUT_TO_STDERR 4
  68 #define RUN_SILENT_EXEC_FAILURE 8
  69 #define RUN_USING_SHELL 16
  70 #define RUN_CLEAN_ON_EXIT 32
  71 int run_command_v_opt(const char **argv, int opt);
  72
  73 /*
  74  * env (the environment) is to be formatted like environ: "VAR=VALUE".
  75  * To unset an environment variable use just "VAR".
  76  */
  77 int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env);
  78
  79 /**
  80  * Execute the given command, capturing its stdout in the given strbuf.
  81  * Returns -1 if starting the command fails or reading fails, and otherwise
  82  * returns the exit code of the command. The output collected in the
  83  * buffer is kept even if the command returns a non-zero exit. The hint field
  84  * gives a starting size for the strbuf allocation.
  85  *
  86  * The fields of "cmd" should be set up as they would for a normal run_command
  87  * invocation. But note that there is no need to set cmd->out; the function
  88  * sets it up for the caller.
  89  */
  90 int capture_command(struct child_process *cmd, struct strbuf *buf, size_t hint);
  91
  92 /*
  93  * The purpose of the following functions is to feed a pipe by running
  94  * a function asynchronously and providing output that the caller reads.
  95  *
  96  * It is expected that no synchronization and mutual exclusion between
  97  * the caller and the feed function is necessary so that the function
  98  * can run in a thread without interfering with the caller.
  99  */
 100 struct async {
 101         /*
 102          * proc reads from in; closes it before return
 103          * proc writes to out; closes it before return
 104          * returns 0 on success, non-zero on failure
 105          */
 106         int (*proc)(int in, int out, void *data);
 107         void *data;
 108         int in;         /* caller writes here and closes it */
 109         int out;        /* caller reads from here and closes it */
 110 #ifdef NO_PTHREADS
 111         pid_t pid;
 112 #else
 113         pthread_t tid;
 114         int proc_in;
 115         int proc_out;
 116 #endif
 117 };
 118
 119 int start_async(struct async *async);
 120 int finish_async(struct async *async);
 121
 122 #endif