]> sigrok.org Git - libserialport.git/blobdiff - serialport.c
use readdir() instead of the deprecated readir_r()
[libserialport.git] / serialport.c
index ab263a95650a51c60ed881d919733378436909bb..d271478250f8588e0bfe03651b25f492a3d8523e 100644 (file)
@@ -2,8 +2,8 @@
  * This file is part of the libserialport project.
  *
  * Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
- * Copyright (C) 2010-2012 Uwe Hermann <uwe@hermann-uwe.de>
- * Copyright (C) 2013 Martin Ling <martin-libserialport@earth.li>
+ * Copyright (C) 2010-2015 Uwe Hermann <uwe@hermann-uwe.de>
+ * Copyright (C) 2013-2015 Martin Ling <martin-libserialport@earth.li>
  * Copyright (C) 2013 Matthias Heidbrink <m-sigrok@heidbrink.biz>
  * Copyright (C) 2014 Aurelien Jacobs <aurel@gnuage.org>
  *
@@ -21,6 +21,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <config.h>
 #include "libserialport.h"
 #include "libserialport_internal.h"
 
@@ -388,12 +389,12 @@ SP_API void sp_free_port_list(struct sp_port **list)
 #ifdef _WIN32
 #define CHECK_PORT_HANDLE() do { \
        if (port->hdl == INVALID_HANDLE_VALUE) \
-               RETURN_ERROR(SP_ERR_ARG, "Invalid port handle"); \
+               RETURN_ERROR(SP_ERR_ARG, "Port not open"); \
 } while (0)
 #else
 #define CHECK_PORT_HANDLE() do { \
        if (port->fd < 0) \
-               RETURN_ERROR(SP_ERR_ARG, "Invalid port fd"); \
+               RETURN_ERROR(SP_ERR_ARG, "Port not open"); \
 } while (0)
 #endif
 #define CHECK_OPEN_PORT() do { \
@@ -758,23 +759,29 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
        }
 
        /* Start write. */
-       if (WriteFile(port->hdl, buf, count, NULL, &port->write_ovl) == 0) {
-               if (GetLastError() == ERROR_IO_PENDING) {
-                       DEBUG("Waiting for write to complete");
-                       GetOverlappedResult(port->hdl, &port->write_ovl, &bytes_written, TRUE);
-                       DEBUG_FMT("Write completed, %d/%d bytes written", bytes_written, count);
-                       RETURN_INT(bytes_written);
-               } else {
-                       RETURN_FAIL("WriteFile() failed");
-               }
-       } else {
+       if (WriteFile(port->hdl, buf, count, NULL, &port->write_ovl)) {
                DEBUG("Write completed immediately");
                RETURN_INT(count);
+       } else if (GetLastError() == ERROR_IO_PENDING) {
+               DEBUG("Waiting for write to complete");
+               if (GetOverlappedResult(port->hdl, &port->write_ovl, &bytes_written, TRUE) == 0) {
+                       if (GetLastError() == ERROR_SEM_TIMEOUT) {
+                               DEBUG("Write timed out");
+                               RETURN_INT(0);
+                       } else {
+                               RETURN_FAIL("GetOverlappedResult() failed");
+                       }
+               }
+               DEBUG_FMT("Write completed, %d/%d bytes written", bytes_written, count);
+               RETURN_INT(bytes_written);
+       } else {
+               RETURN_FAIL("WriteFile() failed");
        }
 #else
        size_t bytes_written = 0;
        unsigned char *ptr = (unsigned char *) buf;
        struct timeval start, delta, now, end = {0, 0};
+       int started = 0;
        fd_set fds;
        int result;
 
@@ -788,20 +795,25 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
                timeradd(&start, &delta, &end);
        }
 
+       FD_ZERO(&fds);
+       FD_SET(port->fd, &fds);
+
        /* Loop until we have written the requested number of bytes. */
        while (bytes_written < count) {
-               /* Wait until space is available. */
-               FD_ZERO(&fds);
-               FD_SET(port->fd, &fds);
-               if (timeout_ms) {
+               /*
+                * Check timeout only if we have run select() at least once,
+                * to avoid any issues if a short timeout is reached before
+                * select() is even run.
+                */
+               if (timeout_ms && started) {
                        gettimeofday(&now, NULL);
-                       if (timercmp(&now, &end, >)) {
-                               DEBUG("Write timed out");
-                               RETURN_INT(bytes_written);
-                       }
+                       if (timercmp(&now, &end, >))
+                               /* Timeout has expired. */
+                               break;
                        timersub(&end, &now, &delta);
                }
                result = select(port->fd + 1, NULL, &fds, NULL, timeout_ms ? &delta : NULL);
+               started = 1;
                if (result < 0) {
                        if (errno == EINTR) {
                                DEBUG("select() call was interrupted, repeating");
@@ -810,8 +822,8 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
                                RETURN_FAIL("select() failed");
                        }
                } else if (result == 0) {
-                       DEBUG("Write timed out");
-                       RETURN_INT(bytes_written);
+                       /* Timeout has expired. */
+                       break;
                }
 
                /* Do write. */
@@ -830,6 +842,9 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
                ptr += result;
        }
 
+       if (bytes_written < count)
+               DEBUG("Write timed out");
+
        RETURN_INT(bytes_written);
 #endif
 }
@@ -921,19 +936,16 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
 /* Restart wait operation if buffer was emptied. */
 static enum sp_return restart_wait_if_needed(struct sp_port *port, unsigned int bytes_read)
 {
-       int ret, bytes_remaining;
+       DWORD errors;
+       COMSTAT comstat;
 
        if (bytes_read == 0)
                RETURN_OK();
 
-       ret = sp_input_waiting(port);
-
-       if (ret < 0)
-               RETURN_CODEVAL(ret);
-
-       bytes_remaining = ret;
+       if (ClearCommError(port->hdl, &errors, &comstat) == 0)
+               RETURN_FAIL("ClearCommError() failed");
 
-       if (bytes_remaining == 0)
+       if (comstat.cbInQue == 0)
                TRY(restart_wait(port));
 
        RETURN_OK();
@@ -965,25 +977,26 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 
        /* Set timeout. */
        if (port->timeouts.ReadIntervalTimeout != 0 ||
+                       port->timeouts.ReadTotalTimeoutMultiplier != 0 ||
                        port->timeouts.ReadTotalTimeoutConstant != timeout_ms) {
                port->timeouts.ReadIntervalTimeout = 0;
+               port->timeouts.ReadTotalTimeoutMultiplier = 0;
                port->timeouts.ReadTotalTimeoutConstant = timeout_ms;
                if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
                        RETURN_FAIL("SetCommTimeouts() failed");
        }
 
        /* Start read. */
-       if (ReadFile(port->hdl, buf, count, NULL, &port->read_ovl) == 0) {
-               if (GetLastError() == ERROR_IO_PENDING) {
-                       DEBUG("Waiting for read to complete");
-                       GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE);
-                       DEBUG_FMT("Read completed, %d/%d bytes read", bytes_read, count);
-               } else {
-                       RETURN_FAIL("ReadFile() failed");
-               }
-       } else {
+       if (ReadFile(port->hdl, buf, count, NULL, &port->read_ovl)) {
                DEBUG("Read completed immediately");
                bytes_read = count;
+       } else if (GetLastError() == ERROR_IO_PENDING) {
+               DEBUG("Waiting for read to complete");
+               if (GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE) == 0)
+                       RETURN_FAIL("GetOverlappedResult() failed");
+               DEBUG_FMT("Read completed, %d/%d bytes read", bytes_read, count);
+       } else {
+               RETURN_FAIL("ReadFile() failed");
        }
 
        TRY(restart_wait_if_needed(port, bytes_read));
@@ -994,6 +1007,7 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
        size_t bytes_read = 0;
        unsigned char *ptr = (unsigned char *) buf;
        struct timeval start, delta, now, end = {0, 0};
+       int started = 0;
        fd_set fds;
        int result;
 
@@ -1007,19 +1021,25 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
                timeradd(&start, &delta, &end);
        }
 
+       FD_ZERO(&fds);
+       FD_SET(port->fd, &fds);
+
        /* Loop until we have the requested number of bytes. */
        while (bytes_read < count) {
-               /* Wait until data is available. */
-               FD_ZERO(&fds);
-               FD_SET(port->fd, &fds);
-               if (timeout_ms) {
+               /*
+                * Check timeout only if we have run select() at least once,
+                * to avoid any issues if a short timeout is reached before
+                * select() is even run.
+                */
+               if (timeout_ms && started) {
                        gettimeofday(&now, NULL);
                        if (timercmp(&now, &end, >))
                                /* Timeout has expired. */
-                               RETURN_INT(bytes_read);
+                               break;
                        timersub(&end, &now, &delta);
                }
                result = select(port->fd + 1, &fds, NULL, NULL, timeout_ms ? &delta : NULL);
+               started = 1;
                if (result < 0) {
                        if (errno == EINTR) {
                                DEBUG("select() call was interrupted, repeating");
@@ -1028,8 +1048,8 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
                                RETURN_FAIL("select() failed");
                        }
                } else if (result == 0) {
-                       DEBUG("Read timed out");
-                       RETURN_INT(bytes_read);
+                       /* Timeout has expired. */
+                       break;
                }
 
                /* Do read. */
@@ -1037,7 +1057,10 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 
                if (result < 0) {
                        if (errno == EAGAIN)
-                               /* This shouldn't happen because we did a select() first, but handle anyway. */
+                               /*
+                                * This shouldn't happen because we did a
+                                * select() first, but handle anyway.
+                                */
                                continue;
                        else
                                /* This is an actual failure. */
@@ -1048,6 +1071,142 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
                ptr += result;
        }
 
+       if (bytes_read < count)
+               DEBUG("Read timed out");
+
+       RETURN_INT(bytes_read);
+#endif
+}
+
+SP_API enum sp_return sp_blocking_read_next(struct sp_port *port, void *buf,
+                                            size_t count, unsigned int timeout_ms)
+{
+       TRACE("%p, %p, %d, %d", port, buf, count, timeout_ms);
+
+       CHECK_OPEN_PORT();
+
+       if (!buf)
+               RETURN_ERROR(SP_ERR_ARG, "Null buffer");
+
+       if (count == 0)
+               RETURN_ERROR(SP_ERR_ARG, "Zero count");
+
+       if (timeout_ms)
+               DEBUG_FMT("Reading next max %d bytes from port %s, timeout %d ms",
+                       count, port->name, timeout_ms);
+       else
+               DEBUG_FMT("Reading next max %d bytes from port %s, no timeout",
+                       count, port->name);
+
+#ifdef _WIN32
+       DWORD bytes_read = 0;
+
+       /* If timeout_ms == 0, set maximum timeout. */
+       DWORD timeout_val = (timeout_ms == 0 ? MAXDWORD - 1 : timeout_ms);
+
+       /* Set timeout. */
+       if (port->timeouts.ReadIntervalTimeout != MAXDWORD ||
+                       port->timeouts.ReadTotalTimeoutMultiplier != MAXDWORD ||
+                       port->timeouts.ReadTotalTimeoutConstant != timeout_val) {
+               port->timeouts.ReadIntervalTimeout = MAXDWORD;
+               port->timeouts.ReadTotalTimeoutMultiplier = MAXDWORD;
+               port->timeouts.ReadTotalTimeoutConstant = timeout_val;
+               if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+                       RETURN_FAIL("SetCommTimeouts() failed");
+       }
+
+       /* Loop until we have at least one byte, or timeout is reached. */
+       while (bytes_read == 0) {
+               /* Start read. */
+               if (ReadFile(port->hdl, buf, count, &bytes_read, &port->read_ovl)) {
+                       DEBUG("Read completed immediately");
+               } else if (GetLastError() == ERROR_IO_PENDING) {
+                       DEBUG("Waiting for read to complete");
+                       if (GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE) == 0)
+                               RETURN_FAIL("GetOverlappedResult() failed");
+                       if (bytes_read > 0) {
+                               DEBUG("Read completed");
+                       } else if (timeout_ms > 0) {
+                               DEBUG("Read timed out");
+                               break;
+                       } else {
+                               DEBUG("Restarting read");
+                       }
+               } else {
+                       RETURN_FAIL("ReadFile() failed");
+               }
+       }
+
+       TRY(restart_wait_if_needed(port, bytes_read));
+
+       RETURN_INT(bytes_read);
+
+#else
+       size_t bytes_read = 0;
+       struct timeval start, delta, now, end = {0, 0};
+       int started = 0;
+       fd_set fds;
+       int result;
+
+       if (timeout_ms) {
+               /* Get time at start of operation. */
+               gettimeofday(&start, NULL);
+               /* Define duration of timeout. */
+               delta.tv_sec = timeout_ms / 1000;
+               delta.tv_usec = (timeout_ms % 1000) * 1000;
+               /* Calculate time at which we should give up. */
+               timeradd(&start, &delta, &end);
+       }
+
+       FD_ZERO(&fds);
+       FD_SET(port->fd, &fds);
+
+       /* Loop until we have at least one byte, or timeout is reached. */
+       while (bytes_read == 0) {
+               /*
+                * Check timeout only if we have run select() at least once,
+                * to avoid any issues if a short timeout is reached before
+                * select() is even run.
+                */
+               if (timeout_ms && started) {
+                       gettimeofday(&now, NULL);
+                       if (timercmp(&now, &end, >))
+                               /* Timeout has expired. */
+                               break;
+                       timersub(&end, &now, &delta);
+               }
+               result = select(port->fd + 1, &fds, NULL, NULL, timeout_ms ? &delta : NULL);
+               started = 1;
+               if (result < 0) {
+                       if (errno == EINTR) {
+                               DEBUG("select() call was interrupted, repeating");
+                               continue;
+                       } else {
+                               RETURN_FAIL("select() failed");
+                       }
+               } else if (result == 0) {
+                       /* Timeout has expired. */
+                       break;
+               }
+
+               /* Do read. */
+               result = read(port->fd, buf, count);
+
+               if (result < 0) {
+                       if (errno == EAGAIN)
+                               /* This shouldn't happen because we did a select() first, but handle anyway. */
+                               continue;
+                       else
+                               /* This is an actual failure. */
+                               RETURN_FAIL("read() failed");
+               }
+
+               bytes_read = result;
+       }
+
+       if (bytes_read == 0)
+               DEBUG("Read timed out");
+
        RETURN_INT(bytes_read);
 #endif
 }
@@ -1069,8 +1228,10 @@ SP_API enum sp_return sp_nonblocking_read(struct sp_port *port, void *buf,
 
        /* Set timeout. */
        if (port->timeouts.ReadIntervalTimeout != MAXDWORD ||
+                       port->timeouts.ReadTotalTimeoutMultiplier != 0 ||
                        port->timeouts.ReadTotalTimeoutConstant != 0) {
                port->timeouts.ReadIntervalTimeout = MAXDWORD;
+               port->timeouts.ReadTotalTimeoutMultiplier = 0;
                port->timeouts.ReadTotalTimeoutConstant = 0;
                if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
                        RETURN_FAIL("SetCommTimeouts() failed");
@@ -1078,10 +1239,11 @@ SP_API enum sp_return sp_nonblocking_read(struct sp_port *port, void *buf,
 
        /* Do read. */
        if (ReadFile(port->hdl, buf, count, NULL, &port->read_ovl) == 0)
-               RETURN_FAIL("ReadFile() failed");
+               if (GetLastError() != ERROR_IO_PENDING)
+                       RETURN_FAIL("ReadFile() failed");
 
        /* Get number of bytes read. */
-       if (GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE) == 0)
+       if (GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, FALSE) == 0)
                RETURN_FAIL("GetOverlappedResult() failed");
 
        TRY(restart_wait_if_needed(port, bytes_read));
@@ -1265,6 +1427,9 @@ 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};
+       int started = 0, timeout_overflow = 0;
        int result, timeout_remaining_ms;
        struct pollfd *pollfds;
        unsigned int i;
@@ -1296,17 +1461,30 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
 
        /* Loop until an event occurs. */
        while (1) {
-               if (timeout_ms) {
+               /*
+                * Check timeout only if we have run poll() at least once,
+                * to avoid any issues if a short timeout is reached before
+                * poll() is even run.
+                */
+               if (!timeout_ms) {
+                       timeout_remaining_ms = -1;
+               } else if (!started) {
+                       timeout_overflow = (timeout_ms > INT_MAX);
+                       timeout_remaining_ms = timeout_overflow ? INT_MAX : timeout_ms;
+               } else {
                        gettimeofday(&now, NULL);
                        if (timercmp(&now, &end, >)) {
                                DEBUG("Wait timed out");
                                break;
                        }
                        timersub(&end, &now, &delta);
+                       if ((timeout_overflow = timercmp(&delta, &max_delta, >)))
+                               delta = max_delta;
                        timeout_remaining_ms = delta.tv_sec * 1000 + delta.tv_usec / 1000;
                }
 
-               result = poll(pollfds, event_set->count, timeout_ms ? timeout_remaining_ms : -1);
+               result = poll(pollfds, event_set->count, timeout_remaining_ms);
+               started = 1;
 
                if (result < 0) {
                        if (errno == EINTR) {
@@ -1318,7 +1496,8 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
                        }
                } else if (result == 0) {
                        DEBUG("poll() timed out");
-                       break;
+                       if (!timeout_overflow)
+                               break;
                } else {
                        DEBUG("poll() completed");
                        break;