Suppress -Wunused-result warnings about write(), again.

Adopt the same solution as in commit aa90e148ca70a235, but this time
let's put the ugliness inside the write_stderr() macro, instead of
expecting each call site to deal with it.  Back-port that decision
into psql/common.c where I got the macro from in the first place.

Per gripe from Peter Eisentraut.

diff --git a/src/bin/pg_dump/parallel.c b/src/bin/pg_dump/parallel.c
index 0d9b2d8d49773808d65b1a046a0292090ce488b0..5f9f8a33ac2b45a080995053931e7e5734bbe870 100644 (file)
--- a/src/bin/pg_dump/parallel.c
+++ b/src/bin/pg_dump/parallel.c
@@ -137,8 +137,18 @@ static volatile DumpSignalInformation signal_info;
 static CRITICAL_SECTION signal_info_lock;
 #endif
 
-/* Used from signal handlers, no buffering */
-#define write_stderr(str)  write(fileno(stderr), str, strlen(str))
+/*
+ * Write a simple string to stderr --- must be safe in a signal handler.
+ * We ignore the write() result since there's not much we could do about it.
+ * Certain compilers make that harder than it ought to be.
+ */
+#define write_stderr(str) \
+   do { \
+       const char *str_ = (str); \
+       int     rc_; \
+       rc_ = write(fileno(stderr), str_, strlen(str_)); \
+       (void) rc_; \
+   } while (0)
 
 
 #ifdef WIN32

diff --git a/src/bin/psql/common.c b/src/bin/psql/common.c
index b81a2c21630654f1184887fa992ca373fa417880..42370c9b19984b47743addef352f2252c020c440 100644 (file)
--- a/src/bin/psql/common.c
+++ b/src/bin/psql/common.c
@@ -156,8 +156,18 @@ static PGcancel *volatile cancelConn = NULL;
 static CRITICAL_SECTION cancelConnLock;
 #endif
 
-/* Used from signal handlers, no buffering */
-#define write_stderr(str)  write(fileno(stderr), str, strlen(str))
+/*
+ * Write a simple string to stderr --- must be safe in a signal handler.
+ * We ignore the write() result since there's not much we could do about it.
+ * Certain compilers make that harder than it ought to be.
+ */
+#define write_stderr(str) \
+   do { \
+       const char *str_ = (str); \
+       int     rc_; \
+       rc_ = write(fileno(stderr), str_, strlen(str_)); \
+       (void) rc_; \
+   } while (0)
 
 
 #ifndef WIN32
@@ -166,7 +176,6 @@ static void
 handle_sigint(SIGNAL_ARGS)
 {
    int         save_errno = errno;
-   int         rc;
    char        errbuf[256];
 
    /* if we are waiting for input, longjmp out of it */
@@ -183,16 +192,11 @@ handle_sigint(SIGNAL_ARGS)
    if (cancelConn != NULL)
    {
        if (PQcancel(cancelConn, errbuf, sizeof(errbuf)))
-       {
-           rc = write_stderr("Cancel request sent\n");
-           (void) rc;          /* ignore errors, nothing we can do here */
-       }
+           write_stderr("Cancel request sent\n");
        else
        {
-           rc = write_stderr("Could not send cancel request: ");
-           (void) rc;          /* ignore errors, nothing we can do here */
-           rc = write_stderr(errbuf);
-           (void) rc;          /* ignore errors, nothing we can do here */
+           write_stderr("Could not send cancel request: ");
+           write_stderr(errbuf);
        }
    }