Also detect whether the current POSIX implementation offers the optional...

Also detect whether the current POSIX implementation offers the optional function posix_fallocate(). If not, switch off the particle streamed logging.

configure.ac

@@ -379,10 +379,16 @@ AX_PTHREAD([LIBS="$PTHREAD_LIBS $LIBS" CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
     or use CPPFLAGS and LDFLAGS if the library is installed in a
     non-standard location.]))
 
+# Check whether POSIX thread barriers are implemented (e.g. OSX does not have them)
 AC_CHECK_LIB(pthread, pthread_barrier_init,
 	     AC_DEFINE([HAVE_PTHREAD_BARRIERS], [1], [The posix library implements barriers]),
 	     AC_MSG_WARN(POSIX implementation does not have barriers. SWIFT will use home-made ones.))
 
+# Check whether POSIX file allocation functions exist (e.g. OSX does not have them)
+AC_CHECK_LIB(pthread, posix_fallocate,
+	     AC_DEFINE([HAVE_POSIX_FALLOCATE], [1], [The posix library implements file allocation functions.]),
+	     AC_MSG_WARN(POSIX implementation does not have file allocation functions.))
+
 # Check for metis. Note AX_LIB_METIS exists, but cannot be configured
 # to be default off (i.e. given no option it tries to locate METIS), so we
 # don't use that.

src/dump.c

@@ -17,9 +17,20 @@
  *
  ******************************************************************************/
 
+/* Config parameters. */
+
 /* Config parameters. */
 #include "../config.h"
 
+#ifdef HAVE_POSIX_FALLOCATE
+
+/* This object's header. */
+#include "dump.h"
+
+/* Local headers. */
+#include "atomic.h"
+#include "error.h"
+
 /* Some standard headers. */
 #include <errno.h>
 #include <fcntl.h>
@@ -29,13 +40,6 @@
 #include <sys/types.h>
 #include <unistd.h>
 
-/* This object's header. */
-#include "dump.h"
-
-/* Local headers. */
-#include "atomic.h"
-#include "error.h"
-
 /**
  * @brief Obtain a chunk of memory from a dump.
  *
@@ -44,7 +48,6 @@
  * @param offset The offset of the returned memory address within the dump file.
  * @return A pointer to the memory-mapped chunk of data.
  */
-
 void *dump_get(struct dump *d, size_t count, size_t *offset) {
   size_t local_offset = atomic_add(&d->count, count);
   *offset = local_offset + d->file_offset;
@@ -54,7 +57,6 @@ void *dump_get(struct dump *d, size_t count, size_t *offset) {
 /**
  * @brief Ensure that at least size bytes are available in the #dump.
  */
-
 void dump_ensure(struct dump *d, size_t size) {
 
   /* If we have enough space already, just bail. */
@@ -88,7 +90,6 @@ void dump_ensure(struct dump *d, size_t size) {
 /**
  * @brief Flush the #dump to disk.
  */
-
 void dump_sync(struct dump *d) {
   if (msync(d->data, d->count, MS_SYNC) != 0)
     error("Failed to sync memory-mapped data.");
@@ -97,7 +98,6 @@ void dump_sync(struct dump *d) {
 /**
  * @brief Finalize the #dump.
  */
-
 void dump_close(struct dump *d) {
   /* Unmap the data in memory. */
   if (munmap(d->data, d->count) != 0) {
@@ -121,7 +121,6 @@ void dump_close(struct dump *d) {
  *                 note that it will be overwritten.
  * @param size The initial buffer size for this #dump.
  */
-
 void dump_init(struct dump *d, const char *filename, size_t size) {
 
   /* Create the output file. */
@@ -151,3 +150,5 @@ void dump_init(struct dump *d, const char *filename, size_t size) {
   d->file_offset = 0;
   d->page_mask = page_mask;
 }
+
+#endif /* HAVE_POSIX_FALLOCATE */

src/dump.h

@@ -19,8 +19,13 @@
 #ifndef SWIFT_DUMP_H
 #define SWIFT_DUMP_H
 
-/* Includes. */
-#include "lock.h"
+/* Config parameters. */
+#include "../config.h"
+
+#ifdef HAVE_POSIX_FALLOCATE /* Are we on a sensible platform? */
+
+/* Standard headers */
+#include <stdlib.h>
 
 /* Some constants. */
 #define dump_grow_ensure_factor 10
@@ -54,4 +59,6 @@ void dump_sync(struct dump *d);
 void dump_close(struct dump *d);
 void *dump_get(struct dump *d, size_t count, size_t *offset);
 
+#endif /* HAVE_POSIX_FALLOCATE */
+
 #endif /* SWIFT_DUMP_H */

src/logger.c

@@ -20,6 +20,8 @@
 /* Config parameters. */
 #include "../config.h"
 
+#ifdef HAVE_POSIX_FALLOCATE /* Are we on a sensible platform? */
+
 /* Some standard headers. */
 #include <stdint.h>
 #include <stdlib.h>
@@ -41,7 +43,6 @@
  *
  * @return The size of the logger message in bytes.
  */
-
 int logger_size(unsigned int mask) {
 
   /* Start with 8 bytes for the header. */
@@ -95,7 +96,6 @@ int logger_size(unsigned int mask) {
  * @param offset Pointer to the offset of the previous log of this particle.
  * @param dump The #dump in which to log the particle data.
  */
-
 void logger_log_part(struct part *p, unsigned int mask, size_t *offset,
                      struct dump *dump) {
 
@@ -176,7 +176,6 @@ void logger_log_part(struct part *p, unsigned int mask, size_t *offset,
  * @param offset Pointer to the offset of the previous log of this particle.
  * @param dump The #dump in which to log the particle data.
  */
-
 void logger_log_gpart(struct gpart *p, unsigned int mask, size_t *offset,
                       struct dump *dump) {
 
@@ -270,7 +269,6 @@ void logger_log_timestamp(unsigned long long int timestamp, size_t *offset,
  *
  * @return The mask containing the values read.
  */
-
 int logger_read_part(struct part *p, size_t *offset, const char *buff) {
 
   /* Jump to the offset. */
@@ -349,7 +347,6 @@ int logger_read_part(struct part *p, size_t *offset, const char *buff) {
  *
  * @return The mask containing the values read.
  */
-
 int logger_read_gpart(struct gpart *p, size_t *offset, const char *buff) {
 
   /* Jump to the offset. */
@@ -416,7 +413,6 @@ int logger_read_gpart(struct gpart *p, size_t *offset, const char *buff) {
  *
  * @return The mask containing the values read.
  */
-
 int logger_read_timestamp(unsigned long long int *t, size_t *offset,
                           const char *buff) {
 
@@ -444,3 +440,5 @@ int logger_read_timestamp(unsigned long long int *t, size_t *offset,
   /* Finally, return the mask of the values we just read. */
   return mask;
 }
+
+#endif /* HAVE_POSIX_FALLOCATE */