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#ifndef NDO_LIBNAGIOS_RUNCMD_H_INCLUDED
#define NDO_LIBNAGIOS_RUNCMD_H_INCLUDED
#include <signal.h>
/**
* @file runcmd.h
* @brief runcmd library function declarations
*
* A simple interface to executing programs from other programs, using an
* optimized and safer popen()-like implementation. It is considered safer in
* that no shell needs to be spawned for simple commands, and the environment
* passed to the execve()'d program is essentially empty.
*
* This code is based on popen.c, which in turn was taken from
* "Advanced Programming in the UNIX Environment" by W. Richard Stevens.
*
* Care has been taken to make sure the functions are async-safe. The exception
* is runcmd_init() which multithreaded applications or plugins must call in a
* non-reentrant manner before calling any other runcmd function.
*
* @note This is inherited from the nagiosplugins project, although
* it might need refactoring for performance later.
* @{
*/
/** Return code bitflags for runcmd_cmd2strv() */
#define RUNCMD_HAS_REDIR (1 << 0) /**< I/O redirection */
#define RUNCMD_HAS_SUBCOMMAND (1 << 1) /**< subcommands present */
#define RUNCMD_HAS_PAREN (1 << 2) /**< parentheses present in command */
#define RUNCMD_HAS_JOBCONTROL (1 << 3) /**< job control stuff present */
#define RUNCMD_HAS_UBSQ (1 << 4) /**< unbalanced single quotes */
#define RUNCMD_HAS_UBDQ (1 << 5) /**< unbalanced double quotes */
#define RUNCMD_HAS_WILDCARD (1 << 6) /**< wildcards present */
#define RUNCMD_HAS_SHVAR (1 << 7) /**< shell variables present */
#define RUNCMD_EFD (-1) /**< Failed to pipe() or open() */
#define RUNCMD_EALLOC (-2) /**< Failed to alloc */
#define RUNCMD_ECMD (-3) /**< Bad command */
#define RUNCMD_EFORK (-4) /**< Failed to fork() */
#define RUNCMD_EINVAL (-5) /**< Invalid parameters */
#define RUNCMD_EWAIT (-6) /**< Failed to wait() */
/**
* Initialize the runcmd library.
*
* Only multi-threaded programs that might launch the first external
* program from multiple threads simultaneously need to bother with
* this, and they must ensure this is called at least once in a non-reentrant
* manner before calling any other runcmd function.
*/
extern void runcmd_init(void);
/**
* Return pid of a command with a specific file descriptor
* @param[in] fd stdout filedescriptor of the child to get pid from
* @return pid of the child, or 0 on errors
*/
extern pid_t runcmd_pid(int fd);
/**
* Return explanation of which system call or operation failed
* @param code Error code returned by a library function
* @return A non-free()'able string explaining where the error occurred
*/
extern const char *runcmd_strerror(int code);
/**
* Start a command from a command string
* @param[in] cmd The command to launch
* @param[out] pfd Child's stdout filedescriptor
* @param[out] pfderr Child's stderr filedescriptor
* @param[in] env Currently ignored for portability
* @param[in] iobreg The callback function to register the iobrokers for the read ends of the pipe
* @param[in] iobregarg The "arg" value to pass to iobroker_register()
*/
extern int runcmd_open(const char *cmd, int *pfd, int *pfderr, char **env,
void (*iobreg)(int, int, void *), void *iobregarg)
__attribute__((__nonnull__(1, 2, 3, 5, 6)));
/**
* Close a command and return its exit status
* @note Don't use this. It's a retarded way to reap children suitable
* only for launching a one-shot program.
*
* @param[in] fd The child's stdout filedescriptor
* @return exit-status of the child, or -1 in case of errors
*/
extern int runcmd_close(int fd);
/**
* Convert a string to a vector of arguments like a shell would
* @note This might have bugs and is only tested to behave similar
* to how /bin/sh does things. For csh or other non bash-ish shells
* there are no guarantees.
* @note The out_argv array has to be large enough to hold all strings
* found in the command.
* @param[in] str The string to convert to an argument vector
* @param[out] out_argc The number of arguments found
* @param[out] out_argv The argument vector
* @return 0 on (great) success, or a bitmask of failure-codes
* representing f.e. unclosed quotes, job control or output redirection.
* See the RUNCMD_HAS_* and their ilk to find out about the flag.
*/
extern int runcmd_cmd2strv(const char *str, int *out_argc, char **out_argv);
/**
* If you're using libnagios to execute a remote command, the
* static pid_t pids is not freed after runcmd_open
* You can call this function when you're sure pids is no longer
* in use, to keep down memory leaks
*/
extern void runcmd_free_pids(void);
/** @} */
/* INCLUDE_runcmd_h__ */
#endif