[libvirt] [PATCHv2 01/16] command: move all docs into .c file

We already have a precedent of function documentation in C files, where it is closer to the implementation (witness libvirt.h vs. libvirt.c); maintaining docs in both files risks docs going stale. While I was at it, I used consistent doxygen style on all comments. * src/util/command.h: Remove duplicate docs, and move unique documentation... * src/util/command.c: ...here. Suggested by Matthias Bolte. --- prereq patch to 2/16 (not directly related to bypass-cache, but I don't want to rebase across this one) v2: no change from v1, previously posted here: https://www.redhat.com/archives/libvir-list/2011-July/msg00879.html src/util/command.c | 371 ++++++++++++++++++++++++++++++++++++++++------------ src/util/command.h | 223 ++------------------------------ 2 files changed, 299 insertions(+), 295 deletions(-) diff --git a/src/util/command.c b/src/util/command.c index 5bc6272..11dd7b0 100644 --- a/src/util/command.c +++ b/src/util/command.c @@ -130,23 +130,25 @@ static int virClearCapabilities(void) # endif -/* virFork() - fork a new process while avoiding various race/deadlock - conditions - - @pid - a pointer to a pid_t that will receive the return value from - fork() - - on return from virFork(), if *pid < 0, the fork failed and there is - no new process. Otherwise, just like fork(), if *pid == 0, it is the - child process returning, and if *pid > 0, it is the parent. - - Even if *pid >= 0, if the return value from virFork() is < 0, it - indicates a failure that occurred in the parent or child process - after the fork. In this case, the child process should call - _exit(EXIT_FAILURE) after doing any additional error reporting. - +/** + * virFork: + * @pid - a pointer to a pid_t that will receive the return value from + * fork() + * + * fork a new process while avoiding various race/deadlock conditions + * + * on return from virFork(), if *pid < 0, the fork failed and there is + * no new process. Otherwise, just like fork(), if *pid == 0, it is the + * child process returning, and if *pid > 0, it is the parent. + * + * Even if *pid >= 0, if the return value from virFork() is < 0, it + * indicates a failure that occurred in the parent or child process + * after the fork. In this case, the child process should call + * _exit(EXIT_FAILURE) after doing any additional error reporting. */ -int virFork(pid_t *pid) { +int +virFork(pid_t *pid) +{ sigset_t oldmask, newmask; struct sigaction sig_action; int saved_errno, ret = -1; @@ -573,6 +575,7 @@ virExecWithHook(const char *const*argv, } /** + * virRun: * @argv NULL terminated argv to run * @status optional variable to return exit status in * @@ -645,8 +648,13 @@ virFork(pid_t *pid) #endif /* WIN32 */ -/* - * Create a new command for named binary +/** + * virCommandNew: + * @binary: program to run + * + * Create a new command for named binary. If @binary is relative, + * it will be found via a PATH search of the parent's PATH (and not + * any altered PATH set by virCommandAddEnv* commands). */ virCommandPtr virCommandNew(const char *binary) @@ -656,9 +664,13 @@ virCommandNew(const char *binary) return virCommandNewArgs(args); } -/* +/** + * virCommandNewArgs: + * @args: array of arguments + * * Create a new command with a NULL terminated - * set of args, taking binary from args[0] + * set of args, taking binary from args[0]. More arguments can + * be added later. @args[0] is handled like @binary of virCommandNew. */ virCommandPtr virCommandNewArgs(const char *const*args) @@ -684,9 +696,14 @@ virCommandNewArgs(const char *const*args) return cmd; } -/* +/** + * virCommandNewArgList: + * @binary: program to run + * @...: additional arguments + * * Create a new command with a NULL terminated - * list of args, starting with the binary to run + * list of args, starting with the binary to run. More arguments can + * be added later. @binary is handled as in virCommandNew. */ virCommandPtr virCommandNewArgList(const char *binary, ...) @@ -730,9 +747,13 @@ virCommandKeepFD(virCommandPtr cmd, int fd, bool transfer) FD_SET(fd, &cmd->transfer); } -/* +/** + * virCommandPreserveFD: + * @cmd: the command to modify + * @fd: fd to mark for inheritance into child + * * Preserve the specified file descriptor - * in the child, instead of closing it. + * in the child, instead of closing it on exec. * The parent is still responsible for managing fd. */ void @@ -741,9 +762,13 @@ virCommandPreserveFD(virCommandPtr cmd, int fd) return virCommandKeepFD(cmd, fd, false); } -/* +/** + * virCommandTransferFD: + * @cmd: the command to modify + * @fd: fd to reassign to the child + * * Transfer the specified file descriptor - * to the child, instead of closing it. + * to the child, instead of closing it on exec. * Close the fd in the parent during Run/RunAsync/Free. */ void @@ -753,8 +778,13 @@ virCommandTransferFD(virCommandPtr cmd, int fd) } -/* - * Save the child PID in a pidfile +/** + * virCommandSetPidFile: + * @cmd: the command to modify + * @pidfile: filename to use + * + * Save the child PID in a pidfile. The pidfile will be populated + * before the exec of the child. */ void virCommandSetPidFile(virCommandPtr cmd, const char *pidfile) @@ -769,8 +799,11 @@ virCommandSetPidFile(virCommandPtr cmd, const char *pidfile) } -/* - * Remove all capabilities from the child +/** + * virCommandClearCaps: + * @cmd: the command to modify + * + * Remove all capabilities from the child, after any hooks have been run. */ void virCommandClearCaps(virCommandPtr cmd) @@ -783,7 +816,11 @@ virCommandClearCaps(virCommandPtr cmd) #if 0 /* XXX Enable if we have a need for capability management. */ -/* +/** + * virCommandAllowCap: + * @cmd: the command to modify + * @capability: what to allow + * * Re-allow a specific capability */ void @@ -799,8 +836,13 @@ virCommandAllowCap(virCommandPtr cmd, #endif /* 0 */ -/* - * Daemonize the child process +/** + * virCommandDaemonize: + * @cmd: the command to modify + * + * Daemonize the child process. The child will have a current working + * directory of /, and must be started with virCommandRun, which will + * complete as soon as the daemon grandchild has started. */ void virCommandDaemonize(virCommandPtr cmd) @@ -811,7 +853,10 @@ virCommandDaemonize(virCommandPtr cmd) cmd->flags |= VIR_EXEC_DAEMON; } -/* +/** + * virCommandNonblockingFDs: + * @cmd: the command to modify + * * Set FDs created by virCommandSetOutputFD and virCommandSetErrorFD * as non-blocking in the parent. */ @@ -824,8 +869,13 @@ virCommandNonblockingFDs(virCommandPtr cmd) cmd->flags |= VIR_EXEC_NONBLOCK; } -/* - * Add an environment variable to the child created by a printf-style format +/** + * virCommandAddEnvFormat: + * @cmd: the command to modify + * @format: format of arguments, end result must be in name=value format + * @...: arguments to be formatted + * + * Add an environment variable to the child created by a printf-style format. */ void virCommandAddEnvFormat(virCommandPtr cmd, const char *format, ...) @@ -854,7 +904,12 @@ virCommandAddEnvFormat(virCommandPtr cmd, const char *format, ...) cmd->env[cmd->nenv++] = env; } -/* +/** + * virCommandAddEnvPair: + * @cmd: the command to modify + * @name: variable name, must not contain = + * @value: value to assign to name + * * Add an environment variable to the child * using separate name & value strings */ @@ -865,7 +920,11 @@ virCommandAddEnvPair(virCommandPtr cmd, const char *name, const char *value) } -/* +/** + * virCommandAddEnvString: + * @cmd: the command to modify + * @str: name=value format + * * Add an environment variable to the child * using a preformatted env string FOO=BAR */ @@ -893,7 +952,11 @@ virCommandAddEnvString(virCommandPtr cmd, const char *str) } -/* +/** + * virCommandAddEnvBuffer: + * @cmd: the command to modify + * @buf: buffer that contains name=value string, which will be reset on return + * * Convert a buffer containing preformatted name=value into an * environment variable of the child. * Correctly transfers memory errors or contents from buf to cmd. @@ -918,7 +981,11 @@ virCommandAddEnvBuffer(virCommandPtr cmd, virBufferPtr buf) } -/* +/** + * virCommandAddEnvPass: + * @cmd: the command to modify + * @name: the name to look up in current environment + * * Pass an environment variable to the child * using current process' value */ @@ -935,9 +1002,12 @@ virCommandAddEnvPass(virCommandPtr cmd, const char *name) } -/* +/** + * virCommandAddEnvPassCommon: + * @cmd: the command to modify + * * Set LC_ALL to C, and propagate other essential environment - * variables from the parent process. + * variables (such as PATH) from the parent process. */ void virCommandAddEnvPassCommon(virCommandPtr cmd) @@ -960,7 +1030,11 @@ virCommandAddEnvPassCommon(virCommandPtr cmd) virCommandAddEnvPass(cmd, "TMPDIR"); } -/* +/** + * virCommandAddArg: + * @cmd: the command to modify + * @val: the argument to add + * * Add a command line argument to the child */ void @@ -987,7 +1061,11 @@ virCommandAddArg(virCommandPtr cmd, const char *val) } -/* +/** + * virCommandAddArgBuffer: + * @cmd: the command to modify + * @buf: buffer that contains argument string, which will be reset on return + * * Convert a buffer into a command line argument to the child. * Correctly transfers memory errors or contents from buf to cmd. */ @@ -1011,8 +1089,13 @@ virCommandAddArgBuffer(virCommandPtr cmd, virBufferPtr buf) } -/* - * Add a command line argument created by a printf-style format +/** + * virCommandAddArgFormat: + * @cmd: the command to modify + * @format: format of arguments, end result must be in name=value format + * @...: arguments to be formatted + * + * Add a command line argument created by a printf-style format. */ void virCommandAddArgFormat(virCommandPtr cmd, const char *format, ...) @@ -1041,7 +1124,12 @@ virCommandAddArgFormat(virCommandPtr cmd, const char *format, ...) cmd->args[cmd->nargs++] = arg; } -/* +/** + * virCommandAddArgPair: + * @cmd: the command to modify + * @name: left half of argument + * @value: right half of argument + * * Add "NAME=VAL" as a single command line argument to the child */ void @@ -1050,7 +1138,11 @@ virCommandAddArgPair(virCommandPtr cmd, const char *name, const char *val) virCommandAddArgFormat(cmd, "%s=%s", name, val); } -/* +/** + * virCommandAddArgSet: + * @cmd: the command to modify + * @vals: array of arguments to add + * * Add a NULL terminated list of args */ void @@ -1086,8 +1178,12 @@ virCommandAddArgSet(virCommandPtr cmd, const char *const*vals) } } -/* - * Add a NULL terminated list of args +/** + * virCommandAddArgList: + * @cmd: the command to modify + * @...: list of arguments to add + * + * Add a NULL terminated list of args. */ void virCommandAddArgList(virCommandPtr cmd, ...) @@ -1125,7 +1221,11 @@ virCommandAddArgList(virCommandPtr cmd, ...) va_end(list); } -/* +/** + * virCommandSetWorkingDirectory: + * @cmd: the command to modify + * @pwd: directory to use + * * Set the working directory of a non-daemon child process, rather * than the parent's working directory. Daemons automatically get / * without using this call. @@ -1147,8 +1247,13 @@ virCommandSetWorkingDirectory(virCommandPtr cmd, const char *pwd) } -/* - * Feed the child's stdin from a string buffer +/** + * virCommandSetInputBuffer: + * @cmd: the command to modify + * @inbuf: string to feed to stdin + * + * Feed the child's stdin from a string buffer. This requires the use + * of virCommandRun(). */ void virCommandSetInputBuffer(virCommandPtr cmd, const char *inbuf) @@ -1168,11 +1273,16 @@ virCommandSetInputBuffer(virCommandPtr cmd, const char *inbuf) } -/* +/** + * virCommandSetOutputBuffer: + * @cmd: the command to modify + * @outbuf: address of variable to store malloced result buffer + * * Capture the child's stdout to a string buffer. *outbuf is * guaranteed to be allocated after successful virCommandRun or * virCommandWait, and is best-effort allocated after failed * virCommandRun; caller is responsible for freeing *outbuf. + * This requires the use of virCommandRun. */ void virCommandSetOutputBuffer(virCommandPtr cmd, char **outbuf) @@ -1192,11 +1302,16 @@ virCommandSetOutputBuffer(virCommandPtr cmd, char **outbuf) } -/* +/** + * virCommandSetErrorBuffer: + * @cmd: the command to modify + * @errbuf: address of variable to store malloced result buffer + * * Capture the child's stderr to a string buffer. *errbuf is * guaranteed to be allocated after successful virCommandRun or * virCommandWait, and is best-effort allocated after failed * virCommandRun; caller is responsible for freeing *errbuf. + * This requires the use of virCommandRun. */ void virCommandSetErrorBuffer(virCommandPtr cmd, char **errbuf) @@ -1216,7 +1331,11 @@ virCommandSetErrorBuffer(virCommandPtr cmd, char **errbuf) } -/* +/** + * virCommandSetInputFD: + * @cmd: the command to modify + * @infd: the descriptor to use + * * Attach a file descriptor to the child's stdin */ void @@ -1240,8 +1359,14 @@ virCommandSetInputFD(virCommandPtr cmd, int infd) } -/* - * Attach a file descriptor to the child's stdout +/** + * virCommandSetOutputFD: + * @cmd: the command to modify + * @outfd: location of output fd + * + * Attach a file descriptor to the child's stdout. If *@outfd is -1 on + * entry, then a pipe will be created and returned in this variable when + * the child is run. Otherwise, *@outfd is used as the output. */ void virCommandSetOutputFD(virCommandPtr cmd, int *outfd) @@ -1259,8 +1384,15 @@ virCommandSetOutputFD(virCommandPtr cmd, int *outfd) } -/* - * Attach a file descriptor to the child's stderr +/** + * virCommandSetErrorFD: + * @cmd: the command to modify + * @errfd: location of error fd + * + * Attach a file descriptor to the child's stderr. If *@errfd is -1 on + * entry, then a pipe will be created and returned in this variable when + * the child is run. Otherwise, *@errfd is used for error collection, + * and may be the same as outfd given to virCommandSetOutputFD(). */ void virCommandSetErrorFD(virCommandPtr cmd, int *errfd) @@ -1278,10 +1410,18 @@ virCommandSetErrorFD(virCommandPtr cmd, int *errfd) } -/* +/** + * virCommandSetPreExecHook: + * @cmd: the command to modify + * @hook: the hook to run + * @opaque: argument to pass to the hook + * * Run HOOK(OPAQUE) in the child as the last thing before changing * directories, dropping capabilities, and executing the new process. * Force the child to fail if HOOK does not return zero. + * + * Since @hook runs in the child, it should be careful to avoid + * any functions that are not async-signal-safe. */ void virCommandSetPreExecHook(virCommandPtr cmd, virExecHook hook, void *opaque) @@ -1299,7 +1439,11 @@ virCommandSetPreExecHook(virCommandPtr cmd, virExecHook hook, void *opaque) } -/* +/** + * virCommandWriteArgLog: + * @cmd: the command to log + * @logfd: where to log the results + * * Call after adding all arguments and environment settings, but before * Run/RunAsync, to immediately output the environment and arguments of * cmd to logfd. If virCommandRun cannot succeed (because of an @@ -1337,7 +1481,10 @@ virCommandWriteArgLog(virCommandPtr cmd, int logfd) } -/* +/** + * virCommandToString: + * @cmd: the command to convert + * * Call after adding all arguments and environment settings, but before * Run/RunAsync, to return a string representation of the environment and * arguments of cmd. If virCommandRun cannot succeed (because of an @@ -1382,10 +1529,13 @@ virCommandToString(virCommandPtr cmd) } -/* +/** + * virCommandTranslateStatus: + * @status: child exit status to translate + * * Translate an exit status into a malloc'd string. Generic helper - * for virCommandRun, virCommandWait, and virPidWait status argument, - * as well as raw waitpid and older virRun status. + * for virCommandRun(), virCommandWait(), virRun(), and virPidWait() + * status argument, as well as raw waitpid(). */ char * virCommandTranslateStatus(int status) @@ -1551,10 +1701,13 @@ cleanup: return ret; } -/* +/** + * virCommandExec: + * @cmd: command to run + * * Exec the command, replacing the current process. Meant to be called - * after already forking / cloning, so does not attempt to daemonize or - * preserve any FDs. + * in the hook after already forking / cloning, so does not attempt to + * daemonize or preserve any FDs. * * Returns -1 on any error executing the command. * Will not return on success. @@ -1587,11 +1740,16 @@ int virCommandExec(virCommandPtr cmd ATTRIBUTE_UNUSED) } #endif -/* +/** + * virCommandRun: + * @cmd: command to run + * @exitstatus: optional status collection + * * Run the command and wait for completion. * Returns -1 on any error executing the * command. Returns 0 if the command executed, - * with the exit status set + * with the exit status set. If @exitstatus is NULL, then the + * child must exit with status 0 for this to succeed. */ int virCommandRun(virCommandPtr cmd, int *exitstatus) @@ -1803,7 +1961,11 @@ virCommandHook(void *data) } -/* +/** + * virCommandRunAsync: + * @cmd: command to start + * @pid: optional variable to track child pid + * * Run the command asynchronously * Returns -1 on any error executing the * command. Returns 0 if the command executed. @@ -1909,11 +2071,16 @@ virCommandRunAsync(virCommandPtr cmd, pid_t *pid) } -/* +/** + * virPidWait: + * @pid: child to wait on + * @exitstatus: optional status collection + * * Wait for a child process to complete. * Return -1 on any error waiting for * completion. Returns 0 if the command - * finished with the exit status set + * finished with the exit status set. If @exitstatus is NULL, then the + * child must exit with status 0 for this to succeed. */ int virPidWait(pid_t pid, int *exitstatus) @@ -1951,11 +2118,16 @@ virPidWait(pid_t pid, int *exitstatus) return 0; } -/* - * Wait for the async command to complete. - * Return -1 on any error waiting for +/** + * virCommandWait: + * @cmd: command to wait on + * @exitstatus: optional status collection + * + * Wait for the command previously started with virCommandRunAsync() + * to complete. Return -1 on any error waiting for * completion. Returns 0 if the command - * finished with the exit status set + * finished with the exit status set. If @exitstatus is NULL, then the + * child must exit with status 0 for this to succeed. */ int virCommandWait(virCommandPtr cmd, int *exitstatus) @@ -2006,11 +2178,15 @@ virCommandWait(virCommandPtr cmd, int *exitstatus) #ifndef WIN32 -/* +/** + * virPidAbort: + * @pid: child process to kill + * * Abort a child process if PID is positive and that child is still * running, without issuing any errors or affecting errno. Designed * for error paths where some but not all paths to the cleanup code - * might have started the child process. + * might have started the child process. If @pid is 0 or negative, + * this does nothing. */ void virPidAbort(pid_t pid) @@ -2063,7 +2239,10 @@ cleanup: errno = saved_errno; } -/* +/** + * virCommandAbort: + * @cmd: command to abort + * * Abort an async command if it is running, without issuing * any errors or affecting errno. Designed for error paths * where some but not all paths to the cleanup code might @@ -2096,6 +2275,15 @@ virCommandAbort(virCommandPtr cmd ATTRIBUTE_UNUSED) #endif +/** + * virCommandRequireHandshake: + * @cmd: command to modify + * + * Request that the child perform a handshake with + * the parent when the hook function has completed + * execution. The child will not exec() until the + * parent has notified + */ void virCommandRequireHandshake(virCommandPtr cmd) { if (!cmd || cmd->has_error) @@ -2125,6 +2313,13 @@ void virCommandRequireHandshake(virCommandPtr cmd) cmd->handshake = true; } +/** + * virCommandHandshakeWait: + * @cmd: command to wait on + * + * Wait for the child to complete execution of its + * hook function. To be called in the parent. + */ int virCommandHandshakeWait(virCommandPtr cmd) { char c; @@ -2178,6 +2373,13 @@ int virCommandHandshakeWait(virCommandPtr cmd) return 0; } +/** + * virCommandHandshakeNotify: + * @cmd: command to resume + * + * Notify the child that it is OK to exec() the + * real binary now. To be called in the parent. + */ int virCommandHandshakeNotify(virCommandPtr cmd) { char c = '1'; @@ -2208,10 +2410,13 @@ int virCommandHandshakeNotify(virCommandPtr cmd) } -/* +/** + * virCommandFree: + * @cmd: optional command to free + * * Release all resources. The only exception is that if you called * virCommandRunAsync with a non-null pid, then the asynchronous child - * is not reaped, and you must call virPidWait() yourself. + * is not reaped, and you must call virPidWait() or virPidAbort() yourself. */ void virCommandFree(virCommandPtr cmd) diff --git a/src/util/command.h b/src/util/command.h index f766839..1386d57 100644 --- a/src/util/command.h +++ b/src/util/command.h @@ -30,34 +30,18 @@ typedef struct _virCommand virCommand; typedef virCommand *virCommandPtr; /* This will execute in the context of the first child - * after fork() but before execve() */ + * after fork() but before execve(). As such, it is unsafe to + * call any function that is not async-signal-safe. */ typedef int (*virExecHook)(void *data); -/* - * Fork wrapper with extra error checking - */ int virFork(pid_t *pid) ATTRIBUTE_RETURN_CHECK; -/* - * Simple synchronous command wrapper - */ int virRun(const char *const*argv, int *status) ATTRIBUTE_RETURN_CHECK; -/* - * Create a new command for named binary - */ virCommandPtr virCommandNew(const char *binary) ATTRIBUTE_NONNULL(1); -/* - * Create a new command with a NULL terminated - * set of args, taking binary from argv[0] - */ virCommandPtr virCommandNewArgs(const char *const*args) ATTRIBUTE_NONNULL(1); -/* - * Create a new command with a NULL terminated - * list of args, starting with the binary to run - */ virCommandPtr virCommandNewArgList(const char *binary, ...) ATTRIBUTE_NONNULL(1) ATTRIBUTE_SENTINEL; @@ -65,310 +49,125 @@ virCommandPtr virCommandNewArgList(const char *binary, ...) * delayed until the Run/RunAsync methods */ -/* - * Preserve the specified file descriptor - * in the child, instead of closing it. - * The parent is still responsible for managing fd. - */ void virCommandPreserveFD(virCommandPtr cmd, int fd); -/* - * Transfer the specified file descriptor - * to the child, instead of closing it. - * Close the fd in the parent during Run/RunAsync/Free. - */ void virCommandTransferFD(virCommandPtr cmd, int fd); -/* - * Save the child PID in a pidfile - */ void virCommandSetPidFile(virCommandPtr cmd, const char *pidfile) ATTRIBUTE_NONNULL(2); -/* - * Remove all capabilities from the child - */ void virCommandClearCaps(virCommandPtr cmd); # if 0 -/* - * Re-allow a specific capability - */ void virCommandAllowCap(virCommandPtr cmd, int capability); # endif -/* - * Daemonize the child process - */ void virCommandDaemonize(virCommandPtr cmd); -/* - * Set FDs created by virCommandSetOutputFD and virCommandSetErrorFD - * as non-blocking in the parent. - */ void virCommandNonblockingFDs(virCommandPtr cmd); -/* - * Add an environment variable to the child created by a printf-style format - */ -void -virCommandAddEnvFormat(virCommandPtr cmd, const char *format, ...) - ATTRIBUTE_NONNULL(2) ATTRIBUTE_FMT_PRINTF(2, 3); +void virCommandAddEnvFormat(virCommandPtr cmd, const char *format, ...) + ATTRIBUTE_NONNULL(2) ATTRIBUTE_FMT_PRINTF(2, 3); -/* - * Add an environment variable to the child - * using separate name & value strings - */ void virCommandAddEnvPair(virCommandPtr cmd, const char *name, const char *value) ATTRIBUTE_NONNULL(2); -/* - * Add an environemnt variable to the child - * using a preformated env string FOO=BAR - */ void virCommandAddEnvString(virCommandPtr cmd, const char *str) ATTRIBUTE_NONNULL(2); -/* - * Convert a buffer containing preformatted name=value into an - * environment variable of the child. - * Correctly transfers memory errors or contents from buf to cmd. - */ void virCommandAddEnvBuffer(virCommandPtr cmd, virBufferPtr buf); -/* - * Pass an environment variable to the child - * using current process' value - */ void virCommandAddEnvPass(virCommandPtr cmd, const char *name) ATTRIBUTE_NONNULL(2); -/* - * Pass a common set of environment variables - * to the child using current process' values - */ + void virCommandAddEnvPassCommon(virCommandPtr cmd); -/* - * Add a command line argument to the child - */ void virCommandAddArg(virCommandPtr cmd, const char *val) ATTRIBUTE_NONNULL(2); -/* - * Convert a buffer into a command line argument to the child. - * Correctly transfers memory errors or contents from buf to cmd. - */ void virCommandAddArgBuffer(virCommandPtr cmd, virBufferPtr buf); -/* - * Add a command line argument created by a printf-style format - */ void virCommandAddArgFormat(virCommandPtr cmd, const char *format, ...) ATTRIBUTE_NONNULL(2) ATTRIBUTE_FMT_PRINTF(2, 3); -/* - * Add a command line argument to the child - */ void virCommandAddArgPair(virCommandPtr cmd, const char *name, const char *val) ATTRIBUTE_NONNULL(2) ATTRIBUTE_NONNULL(3); -/* - * Add a NULL terminated array of args - */ + void virCommandAddArgSet(virCommandPtr cmd, const char *const*vals) ATTRIBUTE_NONNULL(2); -/* - * Add a NULL terminated list of args - */ + void virCommandAddArgList(virCommandPtr cmd, ... /* const char *arg, ..., NULL */) ATTRIBUTE_SENTINEL; -/* - * Set the working directory of a non-daemon child process, rather - * than the parent's working directory. Daemons automatically get / - * without using this call. - */ void virCommandSetWorkingDirectory(virCommandPtr cmd, const char *pwd) ATTRIBUTE_NONNULL(2); -/* - * Feed the child's stdin from a string buffer. - * - * NB: Only works with virCommandRun() - */ void virCommandSetInputBuffer(virCommandPtr cmd, const char *inbuf) ATTRIBUTE_NONNULL(2); -/* - * Capture the child's stdout to a string buffer - * - * NB: Only works with virCommandRun() - */ + void virCommandSetOutputBuffer(virCommandPtr cmd, char **outbuf) ATTRIBUTE_NONNULL(2); -/* - * Capture the child's stderr to a string buffer - * - * NB: Only works with virCommandRun() - */ + void virCommandSetErrorBuffer(virCommandPtr cmd, char **errbuf) ATTRIBUTE_NONNULL(2); -/* - * Set a file descriptor as the child's stdin - */ void virCommandSetInputFD(virCommandPtr cmd, int infd); -/* - * Set a file descriptor as the child's stdout - */ + void virCommandSetOutputFD(virCommandPtr cmd, int *outfd) ATTRIBUTE_NONNULL(2); -/* - * Set a file descriptor as the child's stderr - */ + void virCommandSetErrorFD(virCommandPtr cmd, int *errfd) ATTRIBUTE_NONNULL(2); -/* - * A hook function to run between fork + exec - */ void virCommandSetPreExecHook(virCommandPtr cmd, virExecHook hook, void *opaque) ATTRIBUTE_NONNULL(2); -/* - * Call after adding all arguments and environment settings, but before - * Run/RunAsync, to immediately output the environment and arguments of - * cmd to logfd. If virCommandRun cannot succeed (because of an - * out-of-memory condition while building cmd), nothing will be logged. - */ void virCommandWriteArgLog(virCommandPtr cmd, int logfd); -/* - * Call after adding all arguments and environment settings, but before - * Run/RunAsync, to return a string representation of the environment and - * arguments of cmd. If virCommandRun cannot succeed (because of an - * out-of-memory condition while building cmd), NULL will be returned. - * Caller is responsible for freeing the resulting string. - */ char *virCommandToString(virCommandPtr cmd) ATTRIBUTE_RETURN_CHECK; -/* - * Translate an exit status into a malloc'd string. - */ char *virCommandTranslateStatus(int exitstatus) ATTRIBUTE_RETURN_CHECK; -/* - * Exec the command, replacing the current process. Meant to be called - * after already forking / cloning, so does not attempt to daemonize or - * preserve any FDs. - * - * Returns -1 on any error executing the command. - * Will not return on success. - */ int virCommandExec(virCommandPtr cmd) ATTRIBUTE_RETURN_CHECK; -/* - * Run the command and wait for completion. - * Returns -1 on any error executing the - * command. Returns 0 if the command executed, - * with the exit status set - */ int virCommandRun(virCommandPtr cmd, int *exitstatus) ATTRIBUTE_RETURN_CHECK; -/* - * Run the command asynchronously - * Returns -1 on any error executing the - * command. Returns 0 if the command executed. - * - * There are two approaches to child process cleanup. - * 1. Use auto-cleanup, by passing NULL for pid. The child will be - * auto-reaped by virCommandFree, unless you reap it earlier via - * virCommandWait or virCommandAbort. Good for where cmd is in - * scope for the duration of the child process. - * 2. Use manual cleanup, by passing the address of a pid_t variable - * for pid. While cmd is still in scope, you may reap the child via - * virCommandWait or virCommandAbort. But after virCommandFree, if - * you have not yet reaped the child, then it continues to run until - * you call virPidWait or virPidAbort. - */ int virCommandRunAsync(virCommandPtr cmd, pid_t *pid) ATTRIBUTE_RETURN_CHECK; -/* - * Wait for a child process to complete. - * Return -1 on any error waiting for - * completion. Returns 0 if the command - * finished with the exit status set. - */ int virPidWait(pid_t pid, int *exitstatus) ATTRIBUTE_RETURN_CHECK; -/* - * Wait for the async command to complete. - * Return -1 on any error waiting for - * completion. Returns 0 if the command - * finished with the exit status set - */ int virCommandWait(virCommandPtr cmd, int *exitstatus) ATTRIBUTE_RETURN_CHECK; -/* - * Request that the child perform a handshake with - * the parent when the hook function has completed - * execution. The child will not exec() until the - * parent has notified - */ void virCommandRequireHandshake(virCommandPtr cmd); -/* - * Wait for the child to complete execution of its - * hook function - */ int virCommandHandshakeWait(virCommandPtr cmd) ATTRIBUTE_RETURN_CHECK; -/* - * Notify the child that it is OK to exec() the - * real binary now - */ int virCommandHandshakeNotify(virCommandPtr cmd) ATTRIBUTE_RETURN_CHECK; -/* - * Abort a child process if PID is positive and that child is still - * running, without issuing any errors or affecting errno. Designed - * for error paths where some but not all paths to the cleanup code - * might have started the child process. - */ void virPidAbort(pid_t pid); -/* - * Abort an async command if it is running, without issuing - * any errors or affecting errno. Designed for error paths - * where some but not all paths to the cleanup code might - * have started the child process. - */ void virCommandAbort(virCommandPtr cmd); -/* - * Release all resources. The only exception is that if you called - * virCommandRunAsync with a non-null pid, then the asynchronous child - * is not reaped, and you must call virPidWait() yourself. - */ void virCommandFree(virCommandPtr cmd); - #endif /* __VIR_COMMAND_H__ */ -- 1.7.4.4