shared memory abstraction

configure.ac

@@ -240,7 +240,7 @@ fi
 
 dnl Checks for header files.
 AC_HEADER_STDC
-AC_CHECK_HEADERS(poll.h sys/poll.h sys/uio.h fcntl.h sys/time.h unistd.h sys/audio.h linux/soundcard.h)
+AC_CHECK_HEADERS(poll.h sys/poll.h sys/uio.h fcntl.h sys/time.h unistd.h sys/audio.h linux/soundcard.h sys/shm.h)
 
 dnl Checks for typedefs, structures, and compiler characteristics.
 AC_C_CONST

include/ortp/port.h

@@ -271,7 +271,7 @@ char *ortp_strdup_vprintf(const char *fmt, va_list ap);
 
 int ortp_file_exist(const char *pathname);
 
-/* portable named pipes */
+/* portable named pipes  and shared memory*/
 #if !defined(_WIN32_WCE)
 #ifdef WIN32
 typedef HANDLE ortp_pipe_t;
@@ -296,6 +296,10 @@ int ortp_client_pipe_close(ortp_pipe_t sock);
 
 int ortp_pipe_read(ortp_pipe_t p, uint8_t *buf, int len);
 int ortp_pipe_write(ortp_pipe_t p, const uint8_t *buf, int len);
+
+void *ortp_shm_open(unsigned int keyid, int size, int create);
+void ortp_shm_close(void *memory);
+
 #endif
 
 #ifdef __cplusplus

src/port.c

@@ -32,6 +32,10 @@
 #include <process.h>
 #endif
 
+#ifdef HAVE_SYS_SHM_H
+#include <sys/shm.h>
+#endif
+
 static void *ortp_libc_malloc(size_t sz){
 	return malloc(sz);
 }
@@ -436,6 +440,38 @@ int ortp_client_pipe_close(ortp_socket_t sock){
 	return close(sock);
 }
 
+#ifdef HAVE_SYS_SHM_H
+
+void *ortp_shm_open(unsigned int keyid, int size, int create){
+	key_t key=keyid;
+	void *mem;
+	int fd=shmget(key,size,create ? (IPC_CREAT | 0666) : 0666);
+	if (fd==-1){
+		printf("shmget failed: %s\n",strerror(errno));
+		return NULL;
+	}
+	mem=shmat(fd,NULL,0);
+	if (mem==(void*)-1){
+		printf("shmat() failed: %s", strerror(errno));
+		return NULL;
+	}
+	return mem;
+}
+
+void ortp_shm_close(void *mem){
+	shmdt(mem);
+}
+
+#else
+void *ortp_shm_open(unsigned int keyid, int size, int create){
+	ortp_error("No shared memory support for this OS.");
+}
+
+void ortp_shm_close(void *mem){
+}
+
+
+#endif
 
 #elif defined(WIN32) && !defined(_WIN32_WCE)
 
@@ -528,5 +564,11 @@ int ortp_client_pipe_close(ortp_pipe_t sock){
 	return CloseHandle(sock);
 }
 
+void *ortp_shm_open(unsigned int keyid, int size, int create{
+	return NULL;
+}
+
+void ortp_shm_close(void *mem){
+}
 
 #endif