| #ifndef IOLOOPER_H |
| #define IOLOOPER_H |
| |
| #include <stdint.h> |
| |
| /* An IOLooper is an abstraction for select() */ |
| |
| typedef struct IoLooper IoLooper; |
| |
| IoLooper* iolooper_new(void); |
| void iolooper_free( IoLooper* iol ); |
| void iolooper_reset( IoLooper* iol ); |
| |
| void iolooper_add_read( IoLooper* iol, int fd ); |
| void iolooper_add_write( IoLooper* iol, int fd ); |
| void iolooper_del_read( IoLooper* iol, int fd ); |
| void iolooper_del_write( IoLooper* iol, int fd ); |
| |
| int iolooper_poll( IoLooper* iol ); |
| /* Wrapper around select() |
| * Return: |
| * > 0 in case an I/O has occurred, or < 0 on error, or 0 on timeout with |
| * errno set to ETIMEDOUT. |
| */ |
| int iolooper_wait( IoLooper* iol, int64_t duration ); |
| |
| int iolooper_is_read( IoLooper* iol, int fd ); |
| int iolooper_is_write( IoLooper* iol, int fd ); |
| /* Returns 1 if this IoLooper has one or more file descriptor to interact with */ |
| int iolooper_has_operations( IoLooper* iol ); |
| /* Gets current time in milliseconds. |
| * Return: |
| * Number of milliseconds corresponded to the current time on success, or -1 |
| * on failure. |
| */ |
| int64_t iolooper_now(void); |
| /* Waits for an I/O to occur before specific absolute time. |
| * This routine should be used (instead of iolooper_wait) in cases when multiple |
| * sequential I/O should be completed within given time interval. For instance, |
| * consider the scenario, when "server" does two sequential writes, and "client" |
| * now has to read data transferred with these two distinct writes. It might be |
| * wasteful to do two reads, each with the same (large) timeout. Instead, it |
| * would be better to assign a deadline for both reads before the first read, |
| * and call iolooper_wait_absoulte with the same deadline value: |
| * int64_t deadline = iolooper_now() + TIMEOUT; |
| * if (iolooper_wait_absoulte(iol, deadline)) { |
| * // Process first buffer. |
| * (iolooper_wait_absoulte(iol, deadline)) { |
| * // Process second read |
| * } |
| * } |
| * Param: |
| * iol IoLooper instance for an I/O. |
| * deadline Deadline (absoulte time in milliseconds) before which an I/O should |
| * occur. |
| * Return: |
| * Number of I/O descriptors set in iol, if an I/O has occurred, 0 if no I/O |
| * occurred before the deadline, or -1 on error. |
| */ |
| int iolooper_wait_absolute(IoLooper* iol, int64_t deadline); |
| |
| #endif /* IOLOOPER_H */ |