Nico Huber submitted this change.
i2c_helper_linux.c: Use a fixed-size buffer
Given that the buffer size is known in advance, using malloc() is not
necessary. To avoid open-coding buffer sizes, add some trailing null
characters to `I2C_DEV_PREFIX`, as placeholders for bus number digits.
Finally, replace the now-unnecessary `goto` statements with `return`.
Change-Id: I6060749c6ded10949344caee3cc3943306e74a1c
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/52415
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>
---
M i2c_helper_linux.c
1 file changed, 9 insertions(+), 20 deletions(-)
diff --git a/i2c_helper_linux.c b/i2c_helper_linux.c
index 5c191f9..9383c85 100644
--- a/i2c_helper_linux.c
+++ b/i2c_helper_linux.c
@@ -28,7 +28,8 @@
#include "flash.h"
#include "i2c_helper.h"
-#define I2C_DEV_PREFIX "/dev/i2c-"
+/* Null characters are placeholders for bus number digits */
+#define I2C_DEV_PREFIX "/dev/i2c-\0\0\0"
#define I2C_MAX_BUS 255
int i2c_close(int fd)
@@ -38,11 +39,11 @@
int i2c_open(int bus, uint16_t addr, int force)
{
+ char dev[sizeof(I2C_DEV_PREFIX)] = {0};
+
int ret = -1;
int fd = -1;
- /* Maximum i2c bus number is 255(3 char), +1 for null terminated string. */
- int path_len = strlen(I2C_DEV_PREFIX) + 4;
int request = force ? I2C_SLAVE_FORCE : I2C_SLAVE;
if (bus < 0 || bus > I2C_MAX_BUS) {
@@ -50,38 +51,26 @@
return ret;
}
- char *dev = calloc(1, path_len);
- if (!dev) {
- msg_perr("Unable to allocate space for device name of len %d: %s.\n",
- path_len, strerror(errno));
- goto linux_i2c_open_err;
- }
-
- ret = snprintf(dev, path_len, "%s%d", I2C_DEV_PREFIX, bus);
+ ret = snprintf(dev, sizeof(dev), "%s%d", I2C_DEV_PREFIX, bus);
if (ret < 0) {
msg_perr("Unable to join bus number to device name: %s.\n", strerror(errno));
- goto linux_i2c_open_err;
+ return ret;
}
fd = open(dev, O_RDWR);
if (fd < 0) {
msg_perr("Unable to open I2C device %s: %s.\n", dev, strerror(errno));
- ret = fd;
- goto linux_i2c_open_err;
+ return fd;
}
ret = ioctl(fd, request, addr);
if (ret < 0) {
msg_perr("Unable to set I2C slave address to 0x%02x: %s.\n", addr, strerror(errno));
i2c_close(fd);
- goto linux_i2c_open_err;
+ return ret;
}
-linux_i2c_open_err:
- if (dev)
- free(dev);
-
- return ret ? ret : fd;
+ return fd;
}
int i2c_read(int fd, uint16_t addr, i2c_buffer_t *buf)
To view, visit change 52415. To unsubscribe, or for help writing mail filters, visit settings.