On Mon, 21 Sep 2015, Henrik Austad wrote:
> Check return-value from read/write/ftruncate and remove unused variables.
>
> Signed-off-by: Henrik Austad <haustad@xxxxxxxxx>
> ---
> src/backfire/sendme.c | 8 ++++++--
> src/cyclictest/cyclictest.c | 10 +++++++---
> src/pmqtest/pmqtest.c | 3 ++-
> src/ptsematest/ptsematest.c | 3 ++-
> src/rt-migrate-test/rt-migrate-test.c | 5 +++--
> src/signaltest/signaltest.c | 25 +++++++++++++++----------
> src/sigwaittest/sigwaittest.c | 8 ++++++--
> src/svsematest/svsematest.c | 9 +++++++--
> 8 files changed, 48 insertions(+), 23 deletions(-)
>
> diff --git a/src/backfire/sendme.c b/src/backfire/sendme.c
> index c1854d9..e524fbf 100644
> --- a/src/backfire/sendme.c
> +++ b/src/backfire/sendme.c
> @@ -256,9 +256,13 @@ int main(int argc, char *argv[])
> ts.tv_nsec = (interval % USEC_PER_SEC) * 1000;
>
> gettimeofday(&before, NULL);
> - write(path, sigtest, strlen(sigtest));
> + if (write(path, sigtest, strlen(sigtest)) < 0) {
> + fprintf(stderr, "Could not write sigtest to backfire-path\n");
> + }
> while (after.tv_sec == 0);
> - read(path, timestamp, sizeof(timestamp));
> + if (read(path, timestamp, sizeof(timestamp)) <= 0) {
> + fprintf(stderr, "Trouble reading file backfire-path\n");
> + }
> if (sscanf(timestamp, "%lu,%lu\n", &sendtime.tv_sec,
> &sendtime.tv_usec) != 2)
> break;
> diff --git a/src/cyclictest/cyclictest.c b/src/cyclictest/cyclictest.c
> index 2be72fa..42cd964 100644
> --- a/src/cyclictest/cyclictest.c
> +++ b/src/cyclictest/cyclictest.c
> @@ -439,7 +439,9 @@ static void tracemark(char *fmt, ...)
> va_start(ap, fmt);
> len = vsnprintf(tracebuf, TRACEBUFSIZ, fmt, ap);
> va_end(ap);
> - write(tracemark_fd, tracebuf, len);
> + if (write(tracemark_fd, tracebuf, len) < 0) {
> + err_msg_n(errno, "WARN: could not write to tracebuf");
> + }
> }
>
>
> @@ -452,7 +454,8 @@ static void tracing(int on)
> case KV_26_LT24: prctl(0, 1); break;
> case KV_26_33:
> case KV_30:
> - write(trace_fd, "1", 1);
> + if (write(trace_fd, "1", 1) < 0)
> + err_msg_n(errno, "Could not set trace_fd");
> break;
> default: break;
> }
> @@ -462,7 +465,8 @@ static void tracing(int on)
> case KV_26_LT24: prctl(0, 0); break;
> case KV_26_33:
> case KV_30:
> - write(trace_fd, "0", 1);
> + if (write(trace_fd, "0", 1) < 0)
> + err_msg_n(errno, "Could not set trace_fd");
> break;
> default: break;
> }
> diff --git a/src/pmqtest/pmqtest.c b/src/pmqtest/pmqtest.c
> index 75d5ee8..78eaa9c 100644
> --- a/src/pmqtest/pmqtest.c
> +++ b/src/pmqtest/pmqtest.c
> @@ -210,7 +210,8 @@ void *pmqthread(void *param)
> int tracing_enabled =
> open(tracing_enabled_file, O_WRONLY);
> if (tracing_enabled >= 0) {
> - write(tracing_enabled, "0", 1);
> + if (write(tracing_enabled, "0", 1) < 0)
> + err_msg_n(errno, "WARN: could write to tracing_enabled");
> close(tracing_enabled);
> } else
> snprintf(par->error, sizeof(par->error),
> diff --git a/src/ptsematest/ptsematest.c b/src/ptsematest/ptsematest.c
> index a31c745..f777b38 100644
> --- a/src/ptsematest/ptsematest.c
> +++ b/src/ptsematest/ptsematest.c
> @@ -137,7 +137,8 @@ void *semathread(void *param)
> int tracing_enabled =
> open(tracing_enabled_file, O_WRONLY);
> if (tracing_enabled >= 0) {
> - write(tracing_enabled, "0", 1);
> + if (write(tracing_enabled, "0", 1) < 0)
> + err_msg_n(errno, "WARN: Could not enable tracing.");
> close(tracing_enabled);
> } else
> snprintf(par->error, sizeof(par->error),
> diff --git a/src/rt-migrate-test/rt-migrate-test.c b/src/rt-migrate-test/rt-migrate-test.c
> index 85a78da..1501432 100644
> --- a/src/rt-migrate-test/rt-migrate-test.c
> +++ b/src/rt-migrate-test/rt-migrate-test.c
> @@ -44,7 +44,7 @@
> #include <errno.h>
> #include <sched.h>
> #include <pthread.h>
> -
> +#include "error.h"
> #define gettid() syscall(__NR_gettid)
>
> int nr_tasks;
> @@ -87,7 +87,8 @@ static void ftrace_write(const char *fmt, ...)
> n = vsnprintf(buff, BUFSIZ, fmt, ap);
> va_end(ap);
>
> - write(mark_fd, buff, n);
> + if (write(mark_fd, buff, n) < 0)
> + err_msg_n(errno, "WARN: Could not write to trace_marker.");
> }
>
> #define nano2sec(nan) (nan / 1000000000ULL)
> diff --git a/src/signaltest/signaltest.c b/src/signaltest/signaltest.c
> index 61259a0..8c780b9 100644
> --- a/src/signaltest/signaltest.c
> +++ b/src/signaltest/signaltest.c
> @@ -64,6 +64,11 @@ struct thread_stat {
> int threadstarted;
> int tid;
> };
> +#define SYSTEM_W(x) \
> + if (system((x)) < 0) { \
> + fprintf(stderr, "Trouble running %s\n", (x)); \
> + return NULL; \
> + } \
>
> static int shutdown;
> static int tracelimit = 0;
> @@ -101,16 +106,16 @@ void *signalthread(void *param)
> int first = 1;
>
> if (tracelimit) {
> - system("echo 1 > /proc/sys/kernel/trace_all_cpus");
> - system("echo 1 > /proc/sys/kernel/trace_enabled");
> - system("echo 1 > /proc/sys/kernel/trace_freerunning");
> - system("echo 0 > /proc/sys/kernel/trace_print_at_crash");
> - system("echo 1 > /proc/sys/kernel/trace_user_triggered");
> - system("echo -1 > /proc/sys/kernel/trace_user_trigger_irq");
> - system("echo 0 > /proc/sys/kernel/trace_verbose");
> - system("echo 0 > /proc/sys/kernel/preempt_thresh");
> - system("echo 0 > /proc/sys/kernel/wakeup_timing");
> - system("echo 0 > /proc/sys/kernel/preempt_max_latency");
> + SYSTEM_W("echo 1 > /proc/sys/kernel/trace_all_cpus");
> + SYSTEM_W("echo 1 > /proc/sys/kernel/trace_enabled");
> + SYSTEM_W("echo 1 > /proc/sys/kernel/trace_freerunning");
> + SYSTEM_W("echo 0 > /proc/sys/kernel/trace_print_at_crash");
> + SYSTEM_W("echo 1 > /proc/sys/kernel/trace_user_triggered");
> + SYSTEM_W("echo -1 > /proc/sys/kernel/trace_user_trigger_irq");
> + SYSTEM_W("echo 0 > /proc/sys/kernel/trace_verbose");
> + SYSTEM_W("echo 0 > /proc/sys/kernel/preempt_thresh");
> + SYSTEM_W("echo 0 > /proc/sys/kernel/wakeup_timing");
> + SYSTEM_W("echo 0 > /proc/sys/kernel/preempt_max_latency");
> }
>
> stat->tid = gettid();
> diff --git a/src/sigwaittest/sigwaittest.c b/src/sigwaittest/sigwaittest.c
> index 91fcdaa..abeaa35 100644
> --- a/src/sigwaittest/sigwaittest.c
> +++ b/src/sigwaittest/sigwaittest.c
> @@ -36,6 +36,7 @@
> #include <sys/time.h>
> #include <linux/unistd.h>
> #include <utmpx.h>
> +#include "error.h"
> #include "rt-utils.h"
> #include "rt-get_cpu.h"
>
> @@ -185,7 +186,8 @@ void *semathread(void *param)
> int tracing_enabled =
> open(tracing_enabled_file, O_WRONLY);
> if (tracing_enabled >= 0) {
> - write(tracing_enabled, "0", 1);
> + if (write(tracing_enabled, "0", 1) < 0)
> + err_msg_n(errno, "WARN: Could not disable tracing.");
> close(tracing_enabled);
> } else
> snprintf(par->error, sizeof(par->error),
> @@ -378,7 +380,9 @@ int main(int argc, char *argv[])
> fprintf(stderr, "Could not create shared memory\n");
> return 1;
> }
> - ftruncate(shmem, totalsize);
> + if (ftruncate(shmem, totalsize) < 0)
> + err_msg_n(errno, "WARN: Could not truncate file to %d bytes.", totalsize);
> +
> param = mmap(0, totalsize, PROT_READ|PROT_WRITE, MAP_SHARED,
> shmem, 0);
> if (param == MAP_FAILED) {
> diff --git a/src/svsematest/svsematest.c b/src/svsematest/svsematest.c
> index eeb8285..9d4d2b9 100644
> --- a/src/svsematest/svsematest.c
> +++ b/src/svsematest/svsematest.c
> @@ -191,7 +191,8 @@ void *semathread(void *param)
> int tracing_enabled =
> open(tracing_enabled_file, O_WRONLY);
> if (tracing_enabled >= 0) {
> - write(tracing_enabled, "0", 1);
> + if (write(tracing_enabled, "0", 1))
> + err_msg_n(errno, "WARN: Could not write to tracing_enabled!");
> close(tracing_enabled);
> } else
> snprintf(par->error, sizeof(par->error),
> @@ -431,7 +432,11 @@ int main(int argc, char *argv[])
> fprintf(stderr, "Could not create shared memory\n");
> return 1;
> }
> - ftruncate(shmem, totalsize);
> + if (ftruncate(shmem, totalsize) < 0) {
> + fprintf(stderr, "Could not truncate file to specified size (%d)\n", totalsize);
> + return 1;
> +
> + }
> param = mmap(0, totalsize, PROT_READ|PROT_WRITE, MAP_SHARED,
> shmem, 0);
> if (param == MAP_FAILED) {
> --
After applying your patch, I get this build failure.
gcc -Wall -Wno-nonnull -O2 -DNUMA -o rt-migrate-test rt-migrate-test.o
-lrt -lpthread
rt-migrate-test.o: In function `ftrace_write':
rt-migrate-test.c:(.text+0x1b7): undefined reference to `err_msg_n'
collect2: error: ld returned 1 exit status
Makefile:91: recipe for target 'rt-migrate-test' failed
make: *** [rt-migrate-test] Error 1
I think you should break this up into some smaller patches.
Make sure you are doing something logical if a test fails.
Don't just slap a message on a failure to shut-up the compiler for
not checking. Are these tests that you are actually using?
This needs some work.
Thanks
John
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