Add infrastructure to run a function asynchronously.

This adds start_async() and finish_async(), which runs a function
asynchronously. Communication with the caller happens only via pipes.
For this reason, this implementation forks off a child process that runs
the function.

[sp: Style nit fixed by removing unnecessary block on if condition
     inside of start_async()]

Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This commit is contained in:
Johannes Sixt
2007-10-19 21:48:00 +02:00
committed by Shawn O. Pearce
parent cc41fa8da9
commit 2d22c20830
2 changed files with 65 additions and 8 deletions

View File

@ -43,4 +43,26 @@ int run_command_v_opt_cd(const char **argv, int opt, const char *dir);
*/
int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env);
/*
* The purpose of the following functions is to feed a pipe by running
* a function asynchronously and providing output that the caller reads.
*
* 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.
*/
struct async {
/*
* proc writes to fd and closes it;
* returns 0 on success, non-zero on failure
*/
int (*proc)(int fd, void *data);
void *data;
int out; /* caller reads from here and closes it */
pid_t pid;
};
int start_async(struct async *async);
int finish_async(struct async *async);
#endif