1 files changed, 207 insertions, 0 deletions
diff --git a/libglusterfs/src/glusterfs/run.h b/libglusterfs/src/glusterfs/run.h
new file mode 100644
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+++ b/libglusterfs/src/glusterfs/run.h
@@ -0,0 +1,207 @@
+/*
+  Copyright (c) 2008-2012 Red Hat, Inc. <http://www.redhat.com>
+  This file is part of GlusterFS.
+
+  This file is licensed to you under your choice of the GNU Lesser
+  General Public License, version 3 or any later version (LGPLv3 or
+  later), or the GNU General Public License, version 2 (GPLv2), in all
+  cases as published by the Free Software Foundation.
+*/
+
+#ifndef __RUN_H__
+#define __RUN_H__
+
+#define RUN_PIPE -1
+
+struct runner {
+    char **argv;
+    unsigned argvlen;
+    int runerr;
+    pid_t chpid;
+    int chfd[3];
+    FILE *chio[3];
+};
+
+typedef struct runner runner_t;
+
+/**
+ * initialize runner_t instance.
+ *
+ * @param runner pointer to runner_t instance
+ */
+void
+runinit(runner_t *runner);
+
+/**
+ * get FILE pointer to which child's stdio is redirected.
+ *
+ * @param runner pointer to runner_t instance
+ * @param fd specifies which standard file descriptor is
+ *        is asked for
+ *
+ * @see runner_redir()
+ */
+FILE *
+runner_chio(runner_t *runner, int fd);
+
+/**
+ * add an argument.
+ *
+ * 'arg' is duplicated.
+ *
+ * Errors are deferred, no error handling is necessary.
+ *
+ * @param runner pointer to runner_t instance
+ * @param arg    command line argument
+ */
+void
+runner_add_arg(runner_t *runner, const char *arg);
+
+/**
+ * add a sequence of arguments.
+ *
+ * Variadic function, calls runner_add_arg() on each vararg.
+ * Argument sequence MUST be NULL terminated.
+ *
+ * Errors are deferred, no error handling is necessary.
+ *
+ * @param runner pointer to runner_t instance
+ *
+ * @see runner_add_arg()
+ */
+void
+runner_add_args(runner_t *runner, ...);
+
+/**
+ * add an argument with printf style formatting.
+ *
+ * Errors are deferred, no error handling is necessary.
+ *
+ * @param runner pointer to runner_t instance
+ * @param format printf style format specifier
+ */
+void
+runner_argprintf(runner_t *runner, const char *format, ...)
+    __attribute__((__format__(__printf__, 2, 3)));
+/**
+ * log a message about the command to be run.
+ *
+ * @param runner  pointer to runner_t instance
+ *
+ * @param dom  log domain
+ * @param lvl  log level
+ * @param msg  message with which the command is prefixed in log
+ *
+ * @see gf_log()
+ */
+void
+runner_log(runner_t *runner, const char *dom, gf_loglevel_t lvl,
+           const char *msg);
+
+/**
+ * set up redirection for child.
+ *
+ * @param runner  pointer to runner_t instance
+ *
+ * @param fd      fd of child to redirect (0, 1, or 2)
+ * @param tgt_fd  fd on parent side to redirect to.
+ *                Note that runner_end() will close tgt_fd,
+ *                if user needs it in another context it should
+ *                be dup'd beforehand.
+ *                RUN_PIPE can be used for requiring a
+ *                pipe from child to parent. The FILE
+ *                created for this purpose will be
+ *                accessible via runner_chio() (after
+ *                runner_start() has been invoked).
+ *
+ * @see  runner_start(), dup(2), runner_chio(), runner_start()
+ */
+void
+runner_redir(runner_t *runner, int fd, int tgt_fd);
+
+/**
+ * spawn child with accumulated arg list.
+ *
+ * @param runner  pointer to runner_t instance
+ *
+ * @return  0 on successful spawn
+ *          -1 on failure (either due to earlier errors or execve(2) failing)
+ *
+ * @see runner_cout()
+ */
+int
+runner_start(runner_t *runner);
+
+/**
+ * complete operation and free resources.
+ *
+ * If child exists, waits for it. Redirections will be closed.
+ * Dynamically allocated memory shall be freed.
+ *
+ * @param runner  pointer to runner_t instance
+ *
+ * @return  0 if child terminated successfully
+ *          -1 if there is no running child
+ *          n > 0 if child failed; value to be interpreted as status
+ *                in waitpid(2)
+ *
+ * @see waitpid(2)
+ */
+int
+runner_end(runner_t *runner);
+
+/**
+ * variant of runner_end() which does not free internal data
+ * so that the runner instance can be run again.
+ *
+ * @see runner_end()
+ */
+int
+runner_end_reuse(runner_t *runner);
+
+/**
+ * spawn and child, take it to completion and free resources.
+ *
+ * Essentially it's a concatenation of runner_start() and runner_end()
+ * with simplified return semantics.
+ *
+ * @param runner  pointer to runner_t instance
+ *
+ * @return  0 on success
+ *          -1 on failuire
+ *
+ * @see runner_start(), runner_end()
+ */
+int
+runner_run(runner_t *runner);
+
+/**
+ * variant for runner_run() which does not wait for acknowledgement
+ * from child, and always assumes it succeeds.
+ */
+int
+runner_run_nowait(runner_t *runner);
+
+/**
+ * variant of runner_run() which does not free internal data
+ * so that the runner instance can be run again.
+ *
+ * @see runner_run()
+ */
+int
+runner_run_reuse(runner_t *runner);
+
+/**
+ * run a command with args.
+ *
+ * Variadic function, child process is spawned with
+ * the given sequence of args and waited for.
+ * Argument sequence MUST be NULL terminated.
+ *
+ * @return 0 on success
+ *         -1 on failure
+ */
+int
+runcmd(const char *arg, ...);
+
+#endif