From: Álvaro Neira Ayuso anayuso@sysmocom.de
This patch provide two new functions for reading and writing from the serial interface. I think this two functions makes it easy reading and writing from the serial interface.
Signed-off-by: Alvaro Neira Ayuso anayuso@sysmocom.de --- include/osmocom/core/serial.h | 4 ++++ src/serial.c | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 37 insertions(+)
diff --git a/include/osmocom/core/serial.h b/include/osmocom/core/serial.h index 1640a6d..056010b 100644 --- a/include/osmocom/core/serial.h +++ b/include/osmocom/core/serial.h @@ -33,10 +33,14 @@
#include <termios.h>
+struct msgb; + int osmo_serial_init(const char *dev, speed_t baudrate); int osmo_serial_set_baudrate(int fd, speed_t baudrate); int osmo_serial_set_custom_baudrate(int fd, int baudrate); int osmo_serial_clear_custom_baudrate(int fd); +int osmo_serial_write(int fd, struct msgb *msg); +int osmo_serial_read(int fd, struct msgb *msg, int numbytes);
/*! @} */
diff --git a/src/serial.c b/src/serial.c index 66ee756..818426a 100644 --- a/src/serial.c +++ b/src/serial.c @@ -43,6 +43,7 @@ #endif
#include <osmocom/core/serial.h> +#include <osmocom/core/msgb.h>
#if 0 @@ -226,4 +227,36 @@ osmo_serial_clear_custom_baudrate(int fd) return 0; }
+int +osmo_serial_read(int fd, struct msgb *msg, int numbytes) +{ + int rc, bread = 0; + + while (bread < numbytes) { + rc = read(fd, msg->tail, numbytes - bread); + if (rc < 0) { + msgb_free(msg); + return -1; + } + bread += rc; + msgb_put(msg, rc); + } + + return bread; +} + +int +osmo_serial_write(int fd, struct msgb *msg) +{ + int bwritten = 0, ret = 0; + + bwritten = write(fd, msg->data, msg->len); + if (bwritten < 0 || bwritten < msg->len) { + msgb_free(msg); + ret = -1; + } + + return ret; +} + /*! @} */
Shouldn't this be in libosmocore?
11.02.2014 15:44, Alvaro Neira пишет:
From: Álvaro Neira Ayuso anayuso@sysmocom.de
This patch provide two new functions for reading and writing from the serial interface. I think this two functions makes it easy reading and writing from the serial interface.
Signed-off-by: Alvaro Neira Ayuso anayuso@sysmocom.de
include/osmocom/core/serial.h | 4 ++++ src/serial.c | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 37 insertions(+)
diff --git a/include/osmocom/core/serial.h b/include/osmocom/core/serial.h index 1640a6d..056010b 100644 --- a/include/osmocom/core/serial.h +++ b/include/osmocom/core/serial.h @@ -33,10 +33,14 @@
#include <termios.h>
+struct msgb;
int osmo_serial_init(const char *dev, speed_t baudrate); int osmo_serial_set_baudrate(int fd, speed_t baudrate); int osmo_serial_set_custom_baudrate(int fd, int baudrate); int osmo_serial_clear_custom_baudrate(int fd); +int osmo_serial_write(int fd, struct msgb *msg); +int osmo_serial_read(int fd, struct msgb *msg, int numbytes);
/*! @} */
diff --git a/src/serial.c b/src/serial.c index 66ee756..818426a 100644 --- a/src/serial.c +++ b/src/serial.c @@ -43,6 +43,7 @@ #endif
#include <osmocom/core/serial.h> +#include <osmocom/core/msgb.h>
#if 0 @@ -226,4 +227,36 @@ osmo_serial_clear_custom_baudrate(int fd) return 0; }
+int +osmo_serial_read(int fd, struct msgb *msg, int numbytes) +{
- int rc, bread = 0;
- while (bread < numbytes) {
rc = read(fd, msg->tail, numbytes - bread);if (rc < 0) {msgb_free(msg);return -1;}bread += rc;msgb_put(msg, rc);- }
- return bread;
+}
+int +osmo_serial_write(int fd, struct msgb *msg) +{
- int bwritten = 0, ret = 0;
- bwritten = write(fd, msg->data, msg->len);
- if (bwritten < 0 || bwritten < msg->len) {
msgb_free(msg);ret = -1;- }
- return ret;
+}
/*! @} */
El 11/02/14 16:06, ☎ escribió:
Shouldn't this be in libosmocore?
Yes sorry, i have forgot to put it. Thanks Max
11.02.2014 15:44, Alvaro Neira пишет:
From: Álvaro Neira Ayuso anayuso@sysmocom.de
This patch provide two new functions for reading and writing from the serial interface. I think this two functions makes it easy reading and writing from the serial interface.
Signed-off-by: Alvaro Neira Ayuso anayuso@sysmocom.de
include/osmocom/core/serial.h | 4 ++++ src/serial.c | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 37 insertions(+)
diff --git a/include/osmocom/core/serial.h b/include/osmocom/core/serial.h index 1640a6d..056010b 100644 --- a/include/osmocom/core/serial.h +++ b/include/osmocom/core/serial.h @@ -33,10 +33,14 @@
#include <termios.h>
+struct msgb;
- int osmo_serial_init(const char *dev, speed_t baudrate); int osmo_serial_set_baudrate(int fd, speed_t baudrate); int osmo_serial_set_custom_baudrate(int fd, int baudrate); int osmo_serial_clear_custom_baudrate(int fd);
+int osmo_serial_write(int fd, struct msgb *msg); +int osmo_serial_read(int fd, struct msgb *msg, int numbytes);
/*! @} */
diff --git a/src/serial.c b/src/serial.c index 66ee756..818426a 100644 --- a/src/serial.c +++ b/src/serial.c @@ -43,6 +43,7 @@ #endif
#include <osmocom/core/serial.h> +#include <osmocom/core/msgb.h>
#if 0 @@ -226,4 +227,36 @@ osmo_serial_clear_custom_baudrate(int fd) return 0; }
+int +osmo_serial_read(int fd, struct msgb *msg, int numbytes) +{
- int rc, bread = 0;
- while (bread < numbytes) {
rc = read(fd, msg->tail, numbytes - bread);if (rc < 0) {msgb_free(msg);return -1;}bread += rc;msgb_put(msg, rc);- }
- return bread;
+}
+int +osmo_serial_write(int fd, struct msgb *msg) +{
- int bwritten = 0, ret = 0;
- bwritten = write(fd, msg->data, msg->len);
- if (bwritten < 0 || bwritten < msg->len) {
msgb_free(msg);ret = -1;- }
- return ret;
+}
- /*! @} */
Alvaro Neira wrote:
+++ b/src/serial.c
.
+int +osmo_serial_read(int fd, struct msgb *msg, int numbytes) +{
- int rc, bread = 0;
This is a nice place to add a bounds check..
- while (bread < numbytes) {
rc = read(fd, msg->tail, numbytes - bread);
..so that there is guaranteed room in the msgb for the requested number of bytes.
if (rc < 0) {msgb_free(msg);return -1;}
Are you sure that these functions should destroy the msgb on errors?
Also: What about the bytes which have already been read, in case of error? The proposed code discards those bytes. Is that OK? (I don't know the answer to this; that's why I'm asking.)
+int +osmo_serial_write(int fd, struct msgb *msg) +{
- int bwritten = 0, ret = 0;
- bwritten = write(fd, msg->data, msg->len);
- if (bwritten < 0 || bwritten < msg->len) {
This is incorrect. Both read() and write() may return less than 'count' bytes. You'll need to loop here too to ensure that all data has been written to the port.
msgb_free(msg);
Same question as with the _read function - should this function destroy the msgb on errors?
ret = -1;
I would like the functions to use similar flow. My personal preference for how to handle the return value is the way you use return in the _read function, I find that much nicer than the ret variable in the _write function. But more importantly I think the two should be consistent where possible.
//Peter
-
Alvaro Neira -
Peter Stuge -
Álvaro Neira Ayuso
-
☎