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-rw-r--r--third_party/git/run-command.h250
1 files changed, 6 insertions, 244 deletions
diff --git a/third_party/git/run-command.h b/third_party/git/run-command.h
index 0f3cc73ab672..f769e03f018f 100644
--- a/third_party/git/run-command.h
+++ b/third_party/git/run-command.h
@@ -5,60 +5,8 @@
 
 #include "argv-array.h"
 
-/**
- * The run-command API offers a versatile tool to run sub-processes with
- * redirected input and output as well as with a modified environment
- * and an alternate current directory.
- *
- * A similar API offers the capability to run a function asynchronously,
- * which is primarily used to capture the output that the function
- * produces in the caller in order to process it.
- */
-
-
-/**
- * This describes the arguments, redirections, and environment of a
- * command to run in a sub-process.
- *
- * The caller:
- *
- * 1. allocates and clears (using child_process_init() or
- *    CHILD_PROCESS_INIT) a struct child_process variable;
- * 2. initializes the members;
- * 3. calls start_command();
- * 4. processes the data;
- * 5. closes file descriptors (if necessary; see below);
- * 6. calls finish_command().
- *
- * Special forms of redirection are available by setting these members
- * to 1:
- *
- *  .no_stdin, .no_stdout, .no_stderr: The respective channel is
- *		redirected to /dev/null.
- *
- *	.stdout_to_stderr: stdout of the child is redirected to its
- *		stderr. This happens after stderr is itself redirected.
- *		So stdout will follow stderr to wherever it is
- *		redirected.
- */
 struct child_process {
-
-	/**
-	 * The .argv member is set up as an array of string pointers (NULL
-	 * terminated), of which .argv[0] is the program name to run (usually
-	 * without a path). If the command to run is a git command, set argv[0] to
-	 * the command name without the 'git-' prefix and set .git_cmd = 1.
-	 *
-	 * Note that the ownership of the memory pointed to by .argv stays with the
-	 * caller, but it should survive until `finish_command` completes. If the
-	 * .argv member is NULL, `start_command` will point it at the .args
-	 * `argv_array` (so you may use one or the other, but you must use exactly
-	 * one). The memory in .args will be cleaned up automatically during
-	 * `finish_command` (or during `start_command` when it is unsuccessful).
-	 *
-	 */
 	const char **argv;
-
 	struct argv_array args;
 	struct argv_array env_array;
 	pid_t pid;
@@ -70,8 +18,8 @@ struct child_process {
 
 	/*
 	 * Using .in, .out, .err:
-	 * - Specify 0 for no redirections. No new file descriptor is allocated.
-	 * (child inherits stdin, stdout, stderr from parent).
+	 * - Specify 0 for no redirections (child inherits stdin, stdout,
+	 *   stderr from parent).
 	 * - Specify -1 to have a pipe allocated as follows:
 	 *     .in: returns the writable pipe end; parent writes to it,
 	 *          the readable pipe end becomes child's stdin
@@ -89,43 +37,13 @@ struct child_process {
 	int in;
 	int out;
 	int err;
-
-	/**
-	 * To specify a new initial working directory for the sub-process,
-	 * specify it in the .dir member.
-	 */
 	const char *dir;
-
-	/**
-	 * To modify the environment of the sub-process, specify an array of
-	 * string pointers (NULL terminated) in .env:
-	 *
-	 * - If the string is of the form "VAR=value", i.e. it contains '='
-	 *   the variable is added to the child process's environment.
-	 *
-	 * - If the string does not contain '=', it names an environment
-	 *   variable that will be removed from the child process's environment.
-	 *
-	 * If the .env member is NULL, `start_command` will point it at the
-	 * .env_array `argv_array` (so you may use one or the other, but not both).
-	 * The memory in .env_array will be cleaned up automatically during
-	 * `finish_command` (or during `start_command` when it is unsuccessful).
-	 */
 	const char *const *env;
-
 	unsigned no_stdin:1;
 	unsigned no_stdout:1;
 	unsigned no_stderr:1;
 	unsigned git_cmd:1; /* if this is to be git sub-command */
-
-	/**
-	 * If the program cannot be found, the functions return -1 and set
-	 * errno to ENOENT. Normally, an error message is printed, but if
-	 * .silent_exec_failure is set to 1, no message is printed for this
-	 * special error condition.
-	 */
 	unsigned silent_exec_failure:1;
-
 	unsigned stdout_to_stderr:1;
 	unsigned use_shell:1;
 	unsigned clean_on_exit:1;
@@ -135,63 +53,13 @@ struct child_process {
 };
 
 #define CHILD_PROCESS_INIT { NULL, ARGV_ARRAY_INIT, ARGV_ARRAY_INIT }
-
-/**
- * The functions: child_process_init, start_command, finish_command,
- * run_command, run_command_v_opt, run_command_v_opt_cd_env, child_process_clear
- * do the following:
- *
- * - If a system call failed, errno is set and -1 is returned. A diagnostic
- *   is printed.
- *
- * - If the program was not found, then -1 is returned and errno is set to
- *   ENOENT; a diagnostic is printed only if .silent_exec_failure is 0.
- *
- * - Otherwise, the program is run. If it terminates regularly, its exit
- *   code is returned. No diagnostic is printed, even if the exit code is
- *   non-zero.
- *
- * - If the program terminated due to a signal, then the return value is the
- *   signal number + 128, ie. the same value that a POSIX shell's $? would
- *   report.  A diagnostic is printed.
- *
- */
-
-/**
- * Initialize a struct child_process variable.
- */
 void child_process_init(struct child_process *);
-
-/**
- * Release the memory associated with the struct child_process.
- * Most users of the run-command API don't need to call this
- * function explicitly because `start_command` invokes it on
- * failure and `finish_command` calls it automatically already.
- */
 void child_process_clear(struct child_process *);
-
 int is_executable(const char *name);
 
-/**
- * Start a sub-process. Takes a pointer to a `struct child_process`
- * that specifies the details and returns pipe FDs (if requested).
- * See below for details.
- */
 int start_command(struct child_process *);
-
-/**
- * Wait for the completion of a sub-process that was started with
- * start_command().
- */
 int finish_command(struct child_process *);
-
 int finish_command_in_signal(struct child_process *);
-
-/**
- * A convenience function that encapsulates a sequence of
- * start_command() followed by finish_command(). Takes a pointer
- * to a `struct child_process` that specifies the details.
- */
 int run_command(struct child_process *);
 
 /*
@@ -200,20 +68,6 @@ int run_command(struct child_process *);
  * overwritten by further calls to find_hook and run_hook_*.
  */
 const char *find_hook(const char *name);
-
-/**
- * Run a hook.
- * The first argument is a pathname to an index file, or NULL
- * if the hook uses the default index file or no index is needed.
- * The second argument is the name of the hook.
- * The further arguments correspond to the hook arguments.
- * The last argument has to be NULL to terminate the arguments list.
- * If the hook does not exist or is not executable, the return
- * value will be zero.
- * If it is executable, the hook will be executed and the exit
- * status of the hook is returned.
- * On execution, .stdout_to_stderr and .no_stdin will be set.
- */
 LAST_ARG_MUST_BE_NULL
 int run_hook_le(const char *const *env, const char *name, ...);
 int run_hook_ve(const char *const *env, const char *name, va_list args);
@@ -224,18 +78,6 @@ int run_hook_ve(const char *const *env, const char *name, va_list args);
 #define RUN_SILENT_EXEC_FAILURE 8
 #define RUN_USING_SHELL 16
 #define RUN_CLEAN_ON_EXIT 32
-
-/**
- * Convenience functions that encapsulate a sequence of
- * start_command() followed by finish_command(). The argument argv
- * specifies the program and its arguments. The argument opt is zero
- * or more of the flags `RUN_COMMAND_NO_STDIN`, `RUN_GIT_CMD`,
- * `RUN_COMMAND_STDOUT_TO_STDERR`, or `RUN_SILENT_EXEC_FAILURE`
- * that correspond to the members .no_stdin, .git_cmd,
- * .stdout_to_stderr, .silent_exec_failure of `struct child_process`.
- * The argument dir corresponds the member .dir. The argument env
- * corresponds to the member .env.
- */
 int run_command_v_opt(const char **argv, int opt);
 int run_command_v_opt_tr2(const char **argv, int opt, const char *tr2_class);
 /*
@@ -283,84 +125,15 @@ static inline int capture_command(struct child_process *cmd,
  * It is expected that no synchronization and mutual exclusion between
  * the caller and the feed function is necessary so that the function
  * can run in a thread without interfering with the caller.
- *
- * The caller:
- *
- * 1. allocates and clears (memset(&asy, 0, sizeof(asy));) a
- *    struct async variable;
- * 2. initializes .proc and .data;
- * 3. calls start_async();
- * 4. processes communicates with proc through .in and .out;
- * 5. closes .in and .out;
- * 6. calls finish_async().
- *
- * There are serious restrictions on what the asynchronous function can do
- * because this facility is implemented by a thread in the same address
- * space on most platforms (when pthreads is available), but by a pipe to
- * a forked process otherwise:
- *
- * - It cannot change the program's state (global variables, environment,
- *   etc.) in a way that the caller notices; in other words, .in and .out
- *   are the only communication channels to the caller.
- *
- * - It must not change the program's state that the caller of the
- *   facility also uses.
- *
  */
 struct async {
-
-	/**
-	 * The function pointer in .proc has the following signature:
-	 *
-	 *	int proc(int in, int out, void *data);
-	 *
-	 * - in, out specifies a set of file descriptors to which the function
-	 *  must read/write the data that it needs/produces.  The function
-	 *  *must* close these descriptors before it returns.  A descriptor
-	 *  may be -1 if the caller did not configure a descriptor for that
-	 *  direction.
-	 *
-	 * - data is the value that the caller has specified in the .data member
-	 *  of struct async.
-	 *
-	 * - The return value of the function is 0 on success and non-zero
-	 *  on failure. If the function indicates failure, finish_async() will
-	 *  report failure as well.
-	 *
+	/*
+	 * proc reads from in; closes it before return
+	 * proc writes to out; closes it before return
+	 * returns 0 on success, non-zero on failure
 	 */
 	int (*proc)(int in, int out, void *data);
-
 	void *data;
-
-	/**
-	 * The members .in, .out are used to provide a set of fd's for
-	 * communication between the caller and the callee as follows:
-	 *
-	 * - Specify 0 to have no file descriptor passed.  The callee will
-	 *   receive -1 in the corresponding argument.
-	 *
-	 * - Specify < 0 to have a pipe allocated; start_async() replaces
-	 *   with the pipe FD in the following way:
-	 *
-	 * 	.in: Returns the writable pipe end into which the caller
-	 * 	writes; the readable end of the pipe becomes the function's
-	 * 	in argument.
-	 *
-	 * 	.out: Returns the readable pipe end from which the caller
-	 * 	reads; the writable end of the pipe becomes the function's
-	 * 	out argument.
-	 *
-	 *   The caller of start_async() must close the returned FDs after it
-	 *   has completed reading from/writing from them.
-	 *
-	 * - Specify a file descriptor > 0 to be used by the function:
-	 *
-	 * 	.in: The FD must be readable; it becomes the function's in.
-	 * 	.out: The FD must be writable; it becomes the function's out.
-	 *
-	 *   The specified FD is closed by start_async(), even if it fails to
-	 *   run the function.
-	 */
 	int in;		/* caller writes here and closes it */
 	int out;	/* caller reads from here and closes it */
 #ifdef NO_PTHREADS
@@ -373,19 +146,8 @@ struct async {
 	int isolate_sigpipe;
 };
 
-/**
- * Run a function asynchronously. Takes a pointer to a `struct
- * async` that specifies the details and returns a set of pipe FDs
- * for communication with the function. See below for details.
- */
 int start_async(struct async *async);
-
-/**
- * Wait for the completion of an asynchronous function that was
- * started with start_async().
- */
 int finish_async(struct async *async);
-
 int in_async(void);
 int async_with_fork(void);
 void check_pipe(int err);