* 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>
*
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <config.h>
#include "libserialport.h"
#include "libserialport_internal.h"
RETURN_STRING(port->name);
}
-SP_API char *sp_get_port_description(struct sp_port *port)
+SP_API char *sp_get_port_description(const struct sp_port *port)
{
TRACE("%p", port);
RETURN_STRING(port->description);
}
-SP_API enum sp_transport sp_get_port_transport(struct sp_port *port)
+SP_API enum sp_transport sp_get_port_transport(const struct sp_port *port)
{
TRACE("%p", port);
if (!port)
RETURN_ERROR(SP_ERR_ARG, "Null port");
+ if (!result_ptr)
+ RETURN_ERROR(SP_ERR_ARG, "Null result pointer");
#ifdef _WIN32
HANDLE *handle_ptr = result_ptr;
SP_API enum sp_return sp_list_ports(struct sp_port ***list_ptr)
{
+#ifndef NO_ENUMERATION
struct sp_port **list;
int ret;
+#endif
TRACE("%p", list_ptr);
if (!list_ptr)
RETURN_ERROR(SP_ERR_ARG, "Null result pointer");
+ *list_ptr = NULL;
+
+#ifdef NO_ENUMERATION
+ RETURN_ERROR(SP_ERR_SUPP, "Enumeration not supported on this platform");
+#else
DEBUG("Enumerating ports");
- if (!(list = malloc(sizeof(struct sp_port **))))
+ if (!(list = malloc(sizeof(struct sp_port *))))
RETURN_ERROR(SP_ERR_MEM, "Port list malloc failed");
list[0] = NULL;
-#ifdef NO_ENUMERATION
- ret = SP_ERR_SUPP;
-#else
ret = list_ports(&list);
-#endif
- switch (ret) {
- case SP_OK:
+ if (ret == SP_OK) {
*list_ptr = list;
- RETURN_OK();
- case SP_ERR_SUPP:
- DEBUG_ERROR(SP_ERR_SUPP, "Enumeration not supported on this platform");
- default:
- if (list)
- sp_free_port_list(list);
+ } else {
+ sp_free_port_list(list);
*list_ptr = NULL;
- return ret;
}
+
+ RETURN_CODEVAL(ret);
+#endif
}
SP_API void sp_free_port_list(struct sp_port **list)
data.dcb.fDsrSensitivity = FALSE;
data.dcb.fErrorChar = FALSE;
data.dcb.fNull = FALSE;
- data.dcb.fAbortOnError = TRUE;
+ data.dcb.fAbortOnError = FALSE;
#else
/* Turn off all fancy termios tricks, give us a raw channel. */
data.term.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR | ICRNL | IMAXBEL);
}
SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
- size_t count, unsigned int timeout)
+ size_t count, unsigned int timeout_ms)
{
- TRACE("%p, %p, %d, %d", port, buf, count, timeout);
+ TRACE("%p, %p, %d, %d", port, buf, count, timeout_ms);
CHECK_OPEN_PORT();
if (!buf)
RETURN_ERROR(SP_ERR_ARG, "Null buffer");
- if (timeout)
+ if (timeout_ms)
DEBUG_FMT("Writing %d bytes to port %s, timeout %d ms",
- count, port->name, timeout);
+ count, port->name, timeout_ms);
else
DEBUG_FMT("Writing %d bytes to port %s, no timeout",
count, port->name);
}
/* Set timeout. */
- port->timeouts.WriteTotalTimeoutConstant = timeout;
- if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
- RETURN_FAIL("SetCommTimeouts() failed");
+ if (port->timeouts.WriteTotalTimeoutConstant != timeout_ms) {
+ port->timeouts.WriteTotalTimeoutConstant = timeout_ms;
+ if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+ RETURN_FAIL("SetCommTimeouts() failed");
+ }
/* 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)
+ 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;
- if (timeout) {
+ if (timeout_ms) {
/* Get time at start of operation. */
gettimeofday(&start, NULL);
/* Define duration of timeout. */
- delta.tv_sec = timeout / 1000;
- delta.tv_usec = (timeout % 1000) * 1000;
+ 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 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) {
+ /*
+ * 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 ? &delta : NULL);
+ 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");
RETURN_FAIL("select() failed");
}
} else if (result == 0) {
- DEBUG("Write timed out");
- RETURN_INT(bytes_written);
+ /* Timeout has expired. */
+ break;
}
/* Do write. */
ptr += result;
}
+ if (bytes_written < count)
+ DEBUG("Write timed out");
+
RETURN_INT(bytes_written);
#endif
}
}
/* Set timeout. */
- port->timeouts.WriteTotalTimeoutConstant = 0;
- if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
- RETURN_FAIL("SetCommTimeouts() failed");
+ if (port->timeouts.WriteTotalTimeoutConstant != 0) {
+ port->timeouts.WriteTotalTimeoutConstant = 0;
+ if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+ RETURN_FAIL("SetCommTimeouts() failed");
+ }
/*
* Keep writing data until the OS has to actually start an async IO
#endif
}
+#ifdef _WIN32
+/* Restart wait operation if buffer was emptied. */
+static enum sp_return restart_wait_if_needed(struct sp_port *port, unsigned int bytes_read)
+{
+ DWORD errors;
+ COMSTAT comstat;
+
+ if (bytes_read == 0)
+ RETURN_OK();
+
+ if (ClearCommError(port->hdl, &errors, &comstat) == 0)
+ RETURN_FAIL("ClearCommError() failed");
+
+ if (comstat.cbInQue == 0)
+ TRY(restart_wait(port));
+
+ RETURN_OK();
+}
+#endif
+
SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
- size_t count, unsigned int timeout)
+ size_t count, unsigned int timeout_ms)
{
- TRACE("%p, %p, %d, %d", port, buf, count, timeout);
+ TRACE("%p, %p, %d, %d", port, buf, count, timeout_ms);
CHECK_OPEN_PORT();
if (!buf)
RETURN_ERROR(SP_ERR_ARG, "Null buffer");
- if (timeout)
+ if (timeout_ms)
DEBUG_FMT("Reading %d bytes from port %s, timeout %d ms",
- count, port->name, timeout);
+ count, port->name, timeout_ms);
else
DEBUG_FMT("Reading %d bytes from port %s, no timeout",
count, port->name);
#ifdef _WIN32
DWORD bytes_read = 0;
- DWORD bytes_remaining;
- int ret;
/* Set timeout. */
- port->timeouts.ReadIntervalTimeout = 0;
- port->timeouts.ReadTotalTimeoutConstant = timeout;
- if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
- RETURN_FAIL("SetCommTimeouts() failed");
+ 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");
}
- ret = sp_input_waiting(port);
-
- if (ret < 0)
- RETURN_CODEVAL(ret);
-
- bytes_remaining = ret;
-
- /* Restart wait operation if buffer was emptied. */
- if (bytes_read > 0 && bytes_remaining == 0)
- TRY(restart_wait(port));
+ TRY(restart_wait_if_needed(port, bytes_read));
RETURN_INT(bytes_read);
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;
- if (timeout) {
+ if (timeout_ms) {
/* Get time at start of operation. */
gettimeofday(&start, NULL);
/* Define duration of timeout. */
- delta.tv_sec = timeout / 1000;
- delta.tv_usec = (timeout % 1000) * 1000;
+ 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 the requested number of bytes. */
while (bytes_read < count) {
- /* Wait until data is available. */
- FD_ZERO(&fds);
- FD_SET(port->fd, &fds);
- if (timeout) {
+ /*
+ * 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 ? &delta : NULL);
+ 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");
RETURN_FAIL("select() failed");
}
} else if (result == 0) {
- DEBUG("Read timed out");
- RETURN_INT(bytes_read);
+ /* Timeout has expired. */
+ break;
}
/* Do read. */
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. */
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, 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");
+ 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
}
#ifdef _WIN32
DWORD bytes_read;
- DWORD bytes_remaining;
- int ret;
/* Set timeout. */
- port->timeouts.ReadIntervalTimeout = MAXDWORD;
- port->timeouts.ReadTotalTimeoutConstant = 0;
- if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
- RETURN_FAIL("SetCommTimeouts() failed");
+ 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");
+ }
/* Do read. */
if (ReadFile(port->hdl, buf, count, NULL, &port->read_ovl) == 0)
if (GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE) == 0)
RETURN_FAIL("GetOverlappedResult() failed");
- ret = sp_input_waiting(port);
-
- if (ret < 0)
- RETURN_CODEVAL(ret);
-
- bytes_remaining = ret;
-
- /* Restart wait operation if buffer was emptied. */
- if (bytes_read > 0 && bytes_remaining == 0)
- TRY(restart_wait(port));
+ TRY(restart_wait_if_needed(port, bytes_read));
RETURN_INT(bytes_read);
#else
sizeof(event_handle) * (event_set->count + 1))))
RETURN_ERROR(SP_ERR_MEM, "Handle array realloc() failed");
+ event_set->handles = new_handles;
+
if (!(new_masks = realloc(event_set->masks,
sizeof(enum sp_event) * (event_set->count + 1))))
RETURN_ERROR(SP_ERR_MEM, "Mask array realloc() failed");
- event_set->handles = new_handles;
event_set->masks = new_masks;
((event_handle *) event_set->handles)[event_set->count] = handle;
}
SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
- unsigned int timeout)
+ unsigned int timeout_ms)
{
- TRACE("%p, %d", event_set, timeout);
+ TRACE("%p, %d", event_set, timeout_ms);
if (!event_set)
RETURN_ERROR(SP_ERR_ARG, "Null event set");
#ifdef _WIN32
if (WaitForMultipleObjects(event_set->count, event_set->handles, FALSE,
- timeout ? timeout : INFINITE) == WAIT_FAILED)
+ timeout_ms ? timeout_ms : INFINITE) == WAIT_FAILED)
RETURN_FAIL("WaitForMultipleObjects() failed");
RETURN_OK();
#else
struct timeval start, delta, now, end = {0, 0};
- int result, timeout_remaining;
+ int started = 0;
+ int result, timeout_remaining_ms;
struct pollfd *pollfds;
unsigned int i;
pollfds[i].events |= POLLERR;
}
- if (timeout) {
+ if (timeout_ms) {
/* Get time at start of operation. */
gettimeofday(&start, NULL);
/* Define duration of timeout. */
- delta.tv_sec = timeout / 1000;
- delta.tv_usec = (timeout % 1000) * 1000;
+ 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);
}
/* Loop until an event occurs. */
while (1) {
- if (timeout) {
+ /*
+ * 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_remaining_ms = timeout_ms;
+ } else {
gettimeofday(&now, NULL);
if (timercmp(&now, &end, >)) {
DEBUG("Wait timed out");
break;
}
timersub(&end, &now, &delta);
- timeout_remaining = delta.tv_sec * 1000 + delta.tv_usec / 1000;
+ timeout_remaining_ms = delta.tv_sec * 1000 + delta.tv_usec / 1000;
}
- result = poll(pollfds, event_set->count, timeout ? timeout_remaining : -1);
+ result = poll(pollfds, event_set->count, timeout_remaining_ms);
+ started = 1;
if (result < 0) {
if (errno == EINTR) {
SP_API enum sp_return sp_get_config_##x(const struct sp_port_config *config, \
type *x) { \
TRACE("%p, %p", config, x); \
+ if (!x) \
+ RETURN_ERROR(SP_ERR_ARG, "Null result pointer"); \
if (!config) \
RETURN_ERROR(SP_ERR_ARG, "Null config"); \
*x = config->x; \
TRACE_VOID();
#ifdef _WIN32
- LPVOID message;
+ TCHAR *message;
DWORD error = GetLastError();
- FormatMessage(
+ DWORD length = FormatMessage(
FORMAT_MESSAGE_ALLOCATE_BUFFER |
FORMAT_MESSAGE_FROM_SYSTEM |
FORMAT_MESSAGE_IGNORE_INSERTS,
(LPTSTR) &message,
0, NULL );
+ if (length >= 2 && message[length - 2] == '\r')
+ message[length - 2] = '\0';
+
RETURN_STRING(message);
#else
RETURN_STRING(strerror(errno));
projects / libserialport.git / blobdiff