From ffb84fc1bf1d138d1ac1bb8ece0b7d625f288d97 Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Thu, 20 Feb 2014 09:22:58 +0800 Subject: lib/process: Don't abort stdout reads on EINTR If our read() of the process stdout pipe fails with EINTR (eg, if we receive a SIGCHLD because the process exited), then process_read_stdout_once will return a non-zero exit code, and we'll abort any further stdout collection. Instead, we should check for EINTR, and allow the reads to continue. This change normalises the return value from process_read_stdout_once to return positive on success, negative on failure, and zero on competion. We use a positive return value for the non-error EINTR case. Also, add a pb_log if the read fails for non-EINTR reasons. Signed-off-by: Jeremy Kerr --- test/lib/Makefile.am | 1 + test/lib/test-process-stdout-eintr.c | 57 ++++++++++++++++++++++++++++++++++++ 2 files changed, 58 insertions(+) create mode 100644 test/lib/test-process-stdout-eintr.c (limited to 'test') diff --git a/test/lib/Makefile.am b/test/lib/Makefile.am index ed570af..23bee36 100644 --- a/test/lib/Makefile.am +++ b/test/lib/Makefile.am @@ -32,6 +32,7 @@ check_PROGRAMS = list-test \ test-process-async-stdout \ test-process-parent-stdout \ test-process-both \ + test-process-stdout-eintr \ test-fold TESTS = $(check_PROGRAMS) diff --git a/test/lib/test-process-stdout-eintr.c b/test/lib/test-process-stdout-eintr.c new file mode 100644 index 0000000..b62d570 --- /dev/null +++ b/test/lib/test-process-stdout-eintr.c @@ -0,0 +1,57 @@ + +#include +#include +#include +#include + +#include +#include +#include + +static int do_child(int ppid) +{ + sleep(1); + kill(ppid, SIGCHLD); + printf("forty two\n"); + return 42; +} + +int main(int argc, char **argv) +{ + struct waitset *waitset; + struct process *process; + const char *child_argv[3]; + void *ctx; + + if (argc == 3 && !strcmp(argv[1], "child")) + return do_child(atoi(argv[2])); + + ctx = talloc_new(NULL); + + waitset = waitset_create(ctx); + + process_init(ctx, waitset, false); + + child_argv[0] = argv[0]; + child_argv[1] = "child"; + child_argv[2] = talloc_asprintf(ctx, "%d", getpid()); + child_argv[3] = NULL; + + process = process_create(ctx); + process->path = child_argv[0]; + process->argv = child_argv; + process->keep_stdout = true; + + process_run_sync(process); + + assert(WIFEXITED(process->exit_status)); + assert(WEXITSTATUS(process->exit_status) == 42); + + assert(process->stdout_len == strlen("forty two\n")); + assert(!memcmp(process->stdout_buf, "forty two\n", + process->stdout_len)); + + talloc_free(ctx); + + return EXIT_SUCCESS; +} -- cgit v1.2.1