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mirror of git://sigrok.org/libserialport synced 2023-08-10 21:13:24 +03:00

Abstract all time handling operations.

This commit is contained in:
Martin Ling 2018-09-23 17:10:21 +01:00
parent d9cc984fe7
commit 9a7945af84
2 changed files with 92 additions and 47 deletions

View File

@ -39,6 +39,7 @@
#include <errno.h>
#include <stdio.h>
#include <stdarg.h>
#include <stdbool.h>
#ifdef _WIN32
#include <windows.h>
#include <tchar.h>

View File

@ -56,25 +56,69 @@ static enum sp_return set_config(struct sp_port *port, struct port_data *data,
const struct sp_port_config *config);
#ifndef _WIN32
static void get_time(struct timeval *time)
/* Timing abstraction */
struct time {
struct timeval tv;
};
#define TIME_ZERO {.tv = {0, 0}}
#define TIME_MS(ms) {.tv = {ms / 1000, (ms % 1000) * 1000}}
static void time_get(struct time *time)
{
#ifdef HAVE_CLOCK_GETTIME
struct timespec ts;
if (clock_gettime(CLOCK_MONOTONIC, &ts) == -1)
clock_gettime(CLOCK_REALTIME, &ts);
time->tv_sec = ts.tv_sec;
time->tv_usec = ts.tv_nsec / 1000;
time->tv.tv_sec = ts.tv_sec;
time->tv.tv_usec = ts.tv_nsec / 1000;
#elif defined(__APPLE__)
mach_timebase_info_data_t info;
mach_timebase_info(&info);
uint64_t ticks = mach_absolute_time();
uint64_t ns = (ticks * info.numer) / info.denom;
time->tv_sec = ns / 1000000000;
time->tv_usec = (ns % 1000000000) / 1000;
time->tv.tv_sec = ns / 1000000000;
time->tv.tv_usec = (ns % 1000000000) / 1000;
#else
gettimeofday(time, NULL);
gettimeofday(&time->tv, NULL);
#endif
}
static void time_set_ms(struct time *time, unsigned int ms)
{
time->tv.tv_sec = ms / 1000;
time->tv.tv_usec = (ms % 1000) * 1000;
}
static void time_add(const struct time *a,
const struct time *b, struct time *result)
{
timeradd(&a->tv, &b->tv, &result->tv);
}
static void time_sub(const struct time *a,
const struct time *b, struct time *result)
{
timersub(&a->tv, &b->tv, &result->tv);
}
static bool time_greater(const struct time *a, const struct time *b)
{
return timercmp(&a->tv, &b->tv, >);
}
static void time_as_timeval(const struct time *time, struct timeval *tv)
{
*tv = time->tv;
}
static unsigned int time_as_ms(const struct time *time)
{
return time->tv.tv_sec * 1000 + time->tv.tv_usec / 1000;
}
#endif
SP_API enum sp_return sp_get_port_by_name(const char *portname, struct sp_port **port_ptr)
@ -843,19 +887,18 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
#else
size_t bytes_written = 0;
unsigned char *ptr = (unsigned char *) buf;
struct timeval start, delta, now, end = {0, 0};
struct time start, delta, now, end = TIME_ZERO;
int started = 0;
fd_set fds;
int result;
if (timeout_ms) {
/* Get time at start of operation. */
get_time(&start);
time_get(&start);
/* Define duration of timeout. */
delta.tv_sec = timeout_ms / 1000;
delta.tv_usec = (timeout_ms % 1000) * 1000;
time_set_ms(&delta, timeout_ms);
/* Calculate time at which we should give up. */
timeradd(&start, &delta, &end);
time_add(&start, &delta, &end);
}
FD_ZERO(&fds);
@ -868,14 +911,16 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
* to avoid any issues if a short timeout is reached before
* select() is even run.
*/
struct timeval tv;
if (timeout_ms && started) {
get_time(&now);
if (timercmp(&now, &end, >))
time_get(&now);
if (time_greater(&now, &end))
/* Timeout has expired. */
break;
timersub(&end, &now, &delta);
time_sub(&end, &now, &delta);
time_as_timeval(&delta, &tv);
}
result = select(port->fd + 1, NULL, &fds, NULL, timeout_ms ? &delta : NULL);
result = select(port->fd + 1, NULL, &fds, NULL, timeout_ms ? &tv : NULL);
started = 1;
if (result < 0) {
if (errno == EINTR) {
@ -1062,20 +1107,19 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
#else
size_t bytes_read = 0;
unsigned char *ptr = (unsigned char *)buf;
struct timeval start, delta, now, end = {0, 0};
unsigned char *ptr = (unsigned char *) buf;
struct time start, delta, now, end = TIME_ZERO;
int started = 0;
fd_set fds;
int result;
if (timeout_ms) {
/* Get time at start of operation. */
get_time(&start);
time_get(&start);
/* Define duration of timeout. */
delta.tv_sec = timeout_ms / 1000;
delta.tv_usec = (timeout_ms % 1000) * 1000;
time_set_ms(&delta, timeout_ms);
/* Calculate time at which we should give up. */
timeradd(&start, &delta, &end);
time_add(&start, &delta, &end);
}
FD_ZERO(&fds);
@ -1088,14 +1132,16 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
* to avoid any issues if a short timeout is reached before
* select() is even run.
*/
struct timeval tv;
if (timeout_ms && started) {
get_time(&now);
if (timercmp(&now, &end, >))
time_get(&now);
if (time_greater(&now, &end))
/* Timeout has expired. */
break;
timersub(&end, &now, &delta);
time_sub(&end, &now, &delta);
time_as_timeval(&delta, &tv);
}
result = select(port->fd + 1, &fds, NULL, NULL, timeout_ms ? &delta : NULL);
result = select(port->fd + 1, &fds, NULL, NULL, timeout_ms ? &tv : NULL);
started = 1;
if (result < 0) {
if (errno == EINTR) {
@ -1200,19 +1246,18 @@ SP_API enum sp_return sp_blocking_read_next(struct sp_port *port, void *buf,
#else
size_t bytes_read = 0;
struct timeval start, delta, now, end = {0, 0};
struct time start, delta, now, end = TIME_ZERO;
int started = 0;
fd_set fds;
int result;
if (timeout_ms) {
/* Get time at start of operation. */
get_time(&start);
time_get(&start);
/* Define duration of timeout. */
delta.tv_sec = timeout_ms / 1000;
delta.tv_usec = (timeout_ms % 1000) * 1000;
time_set_ms(&delta, timeout_ms);
/* Calculate time at which we should give up. */
timeradd(&start, &delta, &end);
time_add(&start, &delta, &end);
}
FD_ZERO(&fds);
@ -1225,14 +1270,16 @@ SP_API enum sp_return sp_blocking_read_next(struct sp_port *port, void *buf,
* to avoid any issues if a short timeout is reached before
* select() is even run.
*/
struct timeval tv;
if (timeout_ms && started) {
get_time(&now);
if (timercmp(&now, &end, >))
time_get(&now);
if (time_greater(&now, &end))
/* Timeout has expired. */
break;
timersub(&end, &now, &delta);
time_sub(&end, &now, &delta);
time_as_timeval(&delta, &tv);
}
result = select(port->fd + 1, &fds, NULL, NULL, timeout_ms ? &delta : NULL);
result = select(port->fd + 1, &fds, NULL, NULL, timeout_ms ? &tv : NULL);
started = 1;
if (result < 0) {
if (errno == EINTR) {
@ -1483,10 +1530,8 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
RETURN_OK();
#else
struct timeval start, delta, now, end = {0, 0};
const struct timeval max_delta = {
(INT_MAX / 1000), (INT_MAX % 1000) * 1000
};
struct time start, delta, now, end = TIME_ZERO;
const struct time max_delta = TIME_MS(INT_MAX);
int started = 0, timeout_overflow = 0;
int result, timeout_remaining_ms;
struct pollfd *pollfds;
@ -1509,12 +1554,11 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
if (timeout_ms) {
/* Get time at start of operation. */
get_time(&start);
time_get(&start);
/* Define duration of timeout. */
delta.tv_sec = timeout_ms / 1000;
delta.tv_usec = (timeout_ms % 1000) * 1000;
time_set_ms(&delta, timeout_ms);
/* Calculate time at which we should give up. */
timeradd(&start, &delta, &end);
time_add(&start, &delta, &end);
}
/* Loop until an event occurs. */
@ -1530,15 +1574,15 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
timeout_overflow = (timeout_ms > INT_MAX);
timeout_remaining_ms = timeout_overflow ? INT_MAX : timeout_ms;
} else {
get_time(&now);
if (timercmp(&now, &end, >)) {
time_get(&now);
if (time_greater(&now, &end)) {
DEBUG("Wait timed out");
break;
}
timersub(&end, &now, &delta);
if ((timeout_overflow = timercmp(&delta, &max_delta, >)))
time_sub(&end, &now, &delta);
if ((timeout_overflow = time_greater(&delta, &max_delta)))
delta = max_delta;
timeout_remaining_ms = delta.tv_sec * 1000 + delta.tv_usec / 1000;
timeout_remaining_ms = time_as_ms(&delta);
}
result = poll(pollfds, event_set->count, timeout_remaining_ms);