pulsecore: Transform pa_mempool_new() into a factory method

Soon we're going to have three types of memory pools: POSIX shm_open()
pools, memfd memfd_create() ones, and privately malloc()-ed pools.

Thus introduce annotations for the memory types supported and change
pa_mempool_new() into a factory method based on required memory.

Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>

src/pulsecore/core.c

@@ -69,14 +69,14 @@ pa_core* pa_core_new(pa_mainloop_api *m, bool shared, size_t shm_size) {
     pa_assert(m);
 
     if (shared) {
-        if (!(pool = pa_mempool_new(shared, shm_size))) {
+        if (!(pool = pa_mempool_new(PA_MEM_TYPE_SHARED_POSIX, shm_size))) {
             pa_log_warn("Failed to allocate shared memory pool. Falling back to a normal memory pool.");
             shared = false;
         }
     }
 
     if (!shared) {
-        if (!(pool = pa_mempool_new(shared, shm_size))) {
+        if (!(pool = pa_mempool_new(PA_MEM_TYPE_PRIVATE, shm_size))) {
             pa_log("pa_mempool_new() failed.");
             return NULL;
         }

src/pulsecore/mem.h

@@ -0,0 +1,51 @@
+#ifndef foopulsememhfoo
+#define foopulsememhfoo
+
+/***
+  This file is part of PulseAudio.
+
+  Copyright 2016 Ahmed S. Darwish <darwish.07@gmail.com>
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as
+  published by the Free Software Foundation; either version 2.1 of the
+  License, or (at your option) any later version.
+
+  PulseAudio is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdbool.h>
+
+#include <pulsecore/macro.h>
+
+typedef enum pa_mem_type {
+    PA_MEM_TYPE_SHARED_POSIX,         /* Data is shared and created using POSIX shm_open() */
+    PA_MEM_TYPE_SHARED_MEMFD,         /* Data is shared and created using Linux memfd_create() */
+    PA_MEM_TYPE_PRIVATE,              /* Data is private and created using classic memory allocation
+                                         (posix_memalign(), malloc() or anonymous mmap()) */
+} pa_mem_type_t;
+
+static inline const char *pa_mem_type_to_string(pa_mem_type_t type) {
+    switch (type) {
+    case PA_MEM_TYPE_SHARED_POSIX:
+        return "shared posix-shm";
+    case PA_MEM_TYPE_SHARED_MEMFD:
+        return "shared memfd";
+    case PA_MEM_TYPE_PRIVATE:
+        return "private";
+    }
+
+    pa_assert_not_reached();
+}
+
+static inline bool pa_mem_type_is_shared(pa_mem_type_t t) {
+    return (t == PA_MEM_TYPE_SHARED_POSIX) || (t == PA_MEM_TYPE_SHARED_MEMFD);
+}
+
+#endif

src/pulsecore/memblock.c

@@ -773,7 +773,7 @@ static void memblock_replace_import(pa_memblock *b) {
     pa_mutex_unlock(import->mutex);
 }
 
-pa_mempool* pa_mempool_new(bool shared, size_t size) {
+pa_mempool *pa_mempool_new(pa_mem_type_t type, size_t size) {
     pa_mempool *p;
     char t1[PA_BYTES_SNPRINT_MAX], t2[PA_BYTES_SNPRINT_MAX];
 
@@ -793,13 +793,13 @@ pa_mempool* pa_mempool_new(bool shared, size_t size) {
             p->n_blocks = 2;
     }
 
-    if (pa_shm_create_rw(&p->memory, p->n_blocks * p->block_size, shared, 0700) < 0) {
+    if (pa_shm_create_rw(&p->memory, type, p->n_blocks * p->block_size, 0700) < 0) {
         pa_xfree(p);
         return NULL;
     }
 
     pa_log_debug("Using %s memory pool with %u slots of size %s each, total size is %s, maximum usable slot size is %lu",
-                 p->memory.shared ? "shared" : "private",
+                 pa_mem_type_to_string(type),
                  p->n_blocks,
                  pa_bytes_snprint(t1, sizeof(t1), (unsigned) p->block_size),
                  pa_bytes_snprint(t2, sizeof(t2), (unsigned) (p->n_blocks * p->block_size)),
@@ -922,11 +922,18 @@ void pa_mempool_vacuum(pa_mempool *p) {
     pa_flist_free(list, NULL);
 }
 
+/* No lock necessary */
+bool pa_mempool_is_shared(pa_mempool *p) {
+    pa_assert(p);
+
+    return pa_mem_type_is_shared(p->memory.type);
+}
+
 /* No lock necessary */
 int pa_mempool_get_shm_id(pa_mempool *p, uint32_t *id) {
     pa_assert(p);
 
-    if (!p->memory.shared)
+    if (!pa_mempool_is_shared(p))
         return -1;
 
     *id = p->memory.id;
@@ -934,13 +941,6 @@ int pa_mempool_get_shm_id(pa_mempool *p, uint32_t *id) {
     return 0;
 }
 
-/* No lock necessary */
-bool pa_mempool_is_shared(pa_mempool *p) {
-    pa_assert(p);
-
-    return p->memory.shared;
-}
-
 pa_mempool* pa_mempool_ref(pa_mempool *p) {
     pa_assert(p);
     pa_assert(PA_REFCNT_VALUE(p) > 0);
@@ -1139,7 +1139,7 @@ pa_memexport* pa_memexport_new(pa_mempool *p, pa_memexport_revoke_cb_t cb, void
     pa_assert(p);
     pa_assert(cb);
 
-    if (!p->memory.shared)
+    if (!pa_mempool_is_shared(p))
         return NULL;
 
     e = pa_xnew(pa_memexport, 1);

src/pulsecore/memblock.h

@@ -30,6 +30,7 @@ typedef struct pa_memblock pa_memblock;
 #include <pulse/xmalloc.h>
 #include <pulsecore/atomic.h>
 #include <pulsecore/memchunk.h>
+#include <pulsecore/mem.h>
 
 /* A pa_memblock is a reference counted memory block. PulseAudio
  * passes references to pa_memblocks around instead of copying
@@ -123,7 +124,7 @@ pa_mempool * pa_memblock_get_pool(pa_memblock *b);
 pa_memblock *pa_memblock_will_need(pa_memblock *b);
 
 /* The memory block manager */
-pa_mempool* pa_mempool_new(bool shared, size_t size);
+pa_mempool *pa_mempool_new(pa_mem_type_t type, size_t size);
 void pa_mempool_unref(pa_mempool *p);
 pa_mempool* pa_mempool_ref(pa_mempool *p);
 const pa_mempool_stat* pa_mempool_get_stat(pa_mempool *p);

src/pulsecore/protocol-native.c

@@ -55,6 +55,7 @@
 #include <pulsecore/core-util.h>
 #include <pulsecore/ipacl.h>
 #include <pulsecore/thread-mq.h>
+#include <pulsecore/mem.h>
 
 #include "protocol-native.h"
 
@@ -2621,7 +2622,7 @@ static void setup_srbchannel(pa_native_connection *c) {
         return;
     }
 
-    if (!(c->rw_mempool = pa_mempool_new(true, c->protocol->core->shm_size))) {
+    if (!(c->rw_mempool = pa_mempool_new(PA_MEM_TYPE_SHARED_POSIX, c->protocol->core->shm_size))) {
         pa_log_warn("Disabling srbchannel, reason: Failed to allocate shared "
                     "writable memory pool.");
         return;

src/pulsecore/shm.c

@@ -51,6 +51,7 @@
 #include <pulsecore/core-util.h>
 #include <pulsecore/macro.h>
 #include <pulsecore/atomic.h>
+#include <pulsecore/mem.h>
 
 #include "shm.h"
 
@@ -100,7 +101,7 @@ static char *segment_name(char *fn, size_t l, unsigned id) {
 }
 #endif
 
-int pa_shm_create_rw(pa_shm *m, size_t size, bool shared, mode_t mode) {
+int pa_shm_create_rw(pa_shm *m, pa_mem_type_t type, size_t size, mode_t mode) {
 #ifdef HAVE_SHM_OPEN
     char fn[32];
     int fd = -1;
@@ -119,7 +120,7 @@ int pa_shm_create_rw(pa_shm *m, size_t size, bool shared, mode_t mode) {
     /* Round up to make it page aligned */
     size = PA_PAGE_ALIGN(size);
 
-    if (!shared) {
+    if (!pa_mem_type_is_shared(type)) {
         m->id = 0;
         m->size = size;
 
@@ -184,7 +185,7 @@ int pa_shm_create_rw(pa_shm *m, size_t size, bool shared, mode_t mode) {
 #endif
     }
 
-    m->shared = shared;
+    m->type = type;
 
     return 0;
 
@@ -209,7 +210,7 @@ void pa_shm_free(pa_shm *m) {
     pa_assert(m->ptr != MAP_FAILED);
 #endif
 
-    if (!m->shared) {
+    if (!pa_mem_type_is_shared(m->type)) {
 #ifdef MAP_ANONYMOUS
         if (munmap(m->ptr, m->size) < 0)
             pa_log("munmap() failed: %s", pa_cstrerror(errno));
@@ -325,7 +326,7 @@ static int shm_attach(pa_shm *m, unsigned id, bool writable, bool for_cleanup) {
     }
 
     m->do_unlink = false;
-    m->shared = true;
+    m->type = PA_MEM_TYPE_SHARED_POSIX;
 
     pa_assert_se(pa_close(fd) == 0);
 

src/pulsecore/shm.h

@@ -23,16 +23,17 @@
 #include <sys/types.h>
 
 #include <pulsecore/macro.h>
+#include <pulsecore/mem.h>
 
 typedef struct pa_shm {
+    pa_mem_type_t type;
     unsigned id;
     void *ptr;
     size_t size;
     bool do_unlink:1;
-    bool shared:1;
 } pa_shm;
 
-int pa_shm_create_rw(pa_shm *m, size_t size, bool shared, mode_t mode);
+int pa_shm_create_rw(pa_shm *m, pa_mem_type_t type, size_t size, mode_t mode);
 int pa_shm_attach(pa_shm *m, unsigned id, bool writable);
 
 void pa_shm_punch(pa_shm *m, size_t offset, size_t size);