A first pass at shared memory for Unix. This is still pretty ugly, but I

will clean it up over the next few days.  At least this gives everybody
some idea of where I want the shared memory stuff to go in APR.


git-svn-id: http://svn.apache.org/repos/asf/apr/apr/trunk@59625 13f79535-47bb-0310-9956-ffa450edef68

8 files changed, 247 insertions, 168 deletions

diff --git a/configure.in b/configure.in
index 4d8fe4f3b..364be5a5d 100644
--- a/configure.in
+++ b/configure.in
@@ -5,7 +5,7 @@ OS=`./config.sub $OS`
 
 # These added to allow default directories to be used...
 DEFAULT_OSDIR="unix"
-MODULES="file_io network_io threadproc misc locks time mmap" 
+MODULES="file_io network_io threadproc misc locks time mmap shmem" 
 
 echo "Configuring APR library"
 echo "Platform: ${OS}"
@@ -357,6 +357,15 @@ else
     procpthreadser="0"
 fi
 
+# Shared memory support.  Until I figure out how to do this well, we are hard
+# coding this.  I am hoping to do this more generally ASAP.
+anonymous_shm="1"
+filebased_shm="0"
+keybased_shm="0"
+AC_SUBST(anonymous_shm)
+AC_SUBST(filebased_shm)
+AC_SUBST(keybased_shm)
+
 dnl Start building stuff from our information
 AC_SUBST(LDLIBS)
 AC_SUBST(OPTIM)
@@ -400,6 +409,11 @@ if test "$ac_cv_struct_tm_gmtoff" = "yes"; then
     AC_DEFINE(HAVE_GMTOFF)
 fi
 
+# run the MM config script regardless of whether we are going to use 
+# it or not.  When we have a much better idea of who is using MM, we can
+# run this on a more conditional basis.
+AC_CONFIG_SUBDIRS(shmem/unix/mm)
+
 MAKEFILE1="Makefile lib/Makefile "
 SUBDIRS="lib "
 for dir in $MODULES
diff --git a/include/apr.h.in b/include/apr.h.in
index 298b14415..f70b435df 100644
--- a/include/apr.h.in
+++ b/include/apr.h.in
@@ -40,6 +40,11 @@
 #define APR_USE_PROC_PTHREAD_SERIALIZE    @procpthreadser@ 
 #define APR_USE_PTHREAD_SERIALIZE         @pthreadser@ 
 
+#define APR_USES_ANONYMOUS_SHM            @anonymous_shm@
+#define APR_USES_FILEBASED_SHM            @filebased_shm@
+#define APR_USES_KEYBASED_SHM             @keybased_shm@
+
+
 #define APR_HAVE_IN_ADDR        @have_in_addr@
 #define APR_HAVE_INET_ADDR      @inet_addr@
 #define APR_HAVE_INET_NETWORK   @inet_network@
diff --git a/include/apr_errno.h b/include/apr_errno.h
index fa3d14b12..a5be9532b 100644
--- a/include/apr_errno.h
+++ b/include/apr_errno.h
@@ -107,6 +107,7 @@ typedef int ap_status_t;
 #define APR_ENOTHREAD      (APR_OS_START_ERROR + 12)
 #define APR_ENOTHDKEY      (APR_OS_START_ERROR + 13)
 #define APR_ENOTTHREADSAFE (APR_OS_START_ERROR + 14)
+#define APR_ESHMLOCK       (APR_OS_START_ERROR + 15)
 
 /* APR STATUS VALUES */
 #define APR_INCHILD        (APR_OS_START_STATUS + 1)
@@ -127,6 +128,9 @@ typedef int ap_status_t;
 #define APR_LESS           (APR_OS_START_STATUS + 16)
 #define APR_EQUAL          (APR_OS_START_STATUS + 17)
 #define APR_MORE           (APR_OS_START_STATUS + 18)
+#define APR_ANONYMOUS      (APR_OS_START_STATUS + 19)
+#define APR_FILEBASED      (APR_OS_START_STATUS + 20)
+#define APR_KEYBASED       (APR_OS_START_STATUS + 21)
 
 /* A simple value to be used to initialze a status variable. */
 #define APR_EINIT          (APR_OS_START_STATUS + 16)  
diff --git a/include/apr_shmem.h b/include/apr_shmem.h
index d207c3dff..3595da3b5 100644
--- a/include/apr_shmem.h
+++ b/include/apr_shmem.h
@@ -56,6 +56,7 @@
 #ifndef APR_SHMEM_H
 #define APR_SHMEM_H
 
+#include "apr.h"
 #include "apr_general.h"
 #include "apr_errno.h"
 
@@ -63,19 +64,25 @@
 extern "C" {
 #endif /* __cplusplus */
 
-typedef   struct shmem_t ap_shmem_t
+#if APR_USES_ANONYMOUS_SHM
+typedef   void           ap_shm_name_t;
+#elif APR_USES_FILEBASED_SHM
+typedef   char *         ap_shm_name_t;
+#elif APR_USES_KEYBASED_SHM
+typedef   key_t          ap_shm_name_t;
+#endif
+
+typedef   struct shmem_t ap_shmem_t;
 
-ap_status_t ap_shm_create(ap_shmem_t **, ap_context_t *, ap_size_t, const char *);
-ap_status_t ap_shm_destroy(ap_shmem_t *);
-ap_status_t ap_shm_malloc(void **, ap_shmem_t *, ap_size_t);
-ap_status_t ap_shm_calloc(void **, ap_shmem_t *, ap_size_t, ap_size_t);
-ap_status_t ap_shm_realloc(void **, ap_shmem_t *, ap_size_t);
-ap_status_t ap_shm_free(ap_shmem_t *, void *);
-ap_status_t ap_shm_strdup(char **, ap_shmem_t *, const char *);
-ap_status_t ap_shm_sizeof(ap_shmem_t *, void *, ap_size_t *);
-ap_status_t ap_shm_maxsize(ap_size_t *);
-ap_status_t ap_shm_available(ap_shmem_t *, ap_size_t *);
-ap_status_t ap_shm_child_create(ap_shmem_t**, ap_context_t *, const char *);
+ap_status_t ap_shm_init(ap_shmem_t **m, ap_size_t reqsize, const char *file);
+ap_status_t ap_shm_destroy(ap_shmem_t *m);
+void *ap_shm_malloc(ap_shmem_t *c, ap_size_t reqsize);
+void *ap_shm_calloc(ap_shmem_t *shared, ap_size_t size);
+ap_status_t ap_shm_free(ap_shmem_t *shared, void *free);
+ap_status_t ap_get_shm_name(ap_shmem_t *c, ap_shm_name_t **name);
+ap_status_t ap_set_shm_name(ap_shmem_t *c, ap_shm_name_t *name);
+ap_status_t ap_open_shmem(ap_shmem_t *c);
+ap_status_t ap_shm_avail(ap_shmem_t *c, ap_size_t *avail);
 
 #ifdef __cplusplus
 }
diff --git a/shmem/unix/Makefile.in b/shmem/unix/Makefile.in
index b96e8b404..c30988938 100644
--- a/shmem/unix/Makefile.in
+++ b/shmem/unix/Makefile.in
@@ -11,7 +11,8 @@ LIBS=@LIBS@
 LDFLAGS=@LDFLAGS@ $(LIBS)
 INCDIR=../../inc
 INCDIR1=../../include
-INCLUDES=-I$(INCDIR) -I$(INCDIR1) -Imm -I.
+INCDIR2=../../misc/@OSDIR@
+INCLUDES=-I$(INCDIR) -I$(INCDIR1) -I$(INCDIR2) -Imm -I.
 
 LIB=libshmem.a
 
@@ -32,6 +33,8 @@ $(OBJS): Makefile
 
 $(LIB): $(OBJS)
 	$(RM) -f $@
+	cd mm; make; cd ..
+	cp mm/*.o .
 	$(AR) cr $@ $(OBJS)
 	$(RANLIB) $@
 
diff --git a/shmem/unix/shmem.c b/shmem/unix/shmem.c
index 1263c0cee..6addd28a3 100644
--- a/shmem/unix/shmem.c
+++ b/shmem/unix/shmem.c
@@ -55,116 +55,174 @@
 
 #include "mm.h"
 #include "apr_general.h"
+#include "apr_shmem.h"
 #include "apr_errno.h"
 
 struct shmem_t {
     MM *mm;
-    ap_context_t *cntxt;
 };
 
-ap_status_t ap_shm_create(ap_context_t *cont, ap_size_t size, const char *file,
-                          struct shmem_t **new)
+/* ***APRDOC********************************************************
+ * ap_status_t ap_shm_init(ap_shmem_t *, ap_size_t, char *)
+ *    Create a pool of shared memory for use later.
+ * arg 1) The shared memory block.
+ * arg 2) The size of the shared memory pool.
+ * arg 3) The file to use for the shared memory on platforms that
+ *        require it.
+ */
+ap_status_t ap_shm_init(struct shmem_t **m, ap_size_t reqsize, const char *file)
 {
-    MM *mm = mm_create(size, file);
-
-    if (mm == NULL) {
-        return APR_ENOMEM;
-    }
-    (*new) = (struct shmem_t *)mm_malloc(mm, sizeof(struct shmem_t));
-    if ((*new) == NULL) {
-        return APR_ENOMEM;
+    MM *newmm = mm_create(reqsize, file);
+    if (newmm == NULL) {
+        return errno;
     }
-    (*new)->mm = mm;
-    (*new)->cntxt = cont;
+    (*m) = mm_malloc(newmm, sizeof(struct shmem_t));
+    (*m)->mm = newmm;
     return APR_SUCCESS;
 }
 
-ap_status_t ap_shm_destroy(struct shmem_t *shared)
-{
-    mm_destroy(shared->mm);
-    shared->mm = NULL;
-    return APR_SUCCESS;
-}
-
-ap_status_t ap_shm_malloc(void **entity, struct shmem_t *shared, ap_size_t size)
+/* ***APRDOC********************************************************
+ * ap_status_t ap_shm_destroy(ap_shmem_t *)
+ *    Destroy the shared memory block.
+ * arg 1) The shared memory block to destroy. 
+ */
+ap_status_t ap_shm_destroy(struct shmem_t *m)
 {
-    entity = mm_malloc(shared->mm, size);
-    if (entity == NULL) {
-        return APR_ENOMEM;
-    }
+    mm_destroy(m->mm);
+    m->mm = NULL;
     return APR_SUCCESS;
 }
 
-ap_status_t ap_shm_calloc(struct shmem_t *shared, ap_size_t num, 
-                          ap_size_t size, void **entity)
+/* ***APRDOC********************************************************
+ * ap_status_t ap_shm_malloc(ap_shmem_t *, ap_size_t)
+ *    allocate memory from the block of shared memory.
+ * arg 1) The shared memory block to destroy. 
+ * arg 2) How much memory to allocate
+ */
+void *ap_shm_malloc(struct shmem_t *c, ap_size_t reqsize)
 {
-    entity = mm_calloc(shared->mm, num, size);
-    if (entity == NULL) {
-        return APR_ENOMEM;
+    if (c->mm == NULL) {
+        return NULL;
     }
-    return APR_SUCCESS;
+    return mm_malloc(c->mm, reqsize);
 }
 
-ap_status_t ap_shm_realloc(void **entity, struct shmem_t *shared, ap_size_t size)
+/* ***APRDOC********************************************************
+ * ap_status_t ap_shm_calloc(ap_shmem_t *, ap_size_t)
+ *    allocate memory from the block of shared memory and initialize it
+ *    to zero.
+ * arg 1) The shared memory block to destroy. 
+ * arg 2) How much memory to allocate
+ */
+void *ap_shm_calloc(struct shmem_t *shared, ap_size_t size) 
 {
-    void *new;
-
-    new = mm_realloc(shared->mm, *entity, size);
-    if (new == NULL) {
-        return APR_ENOMEM;
+    if (shared == NULL) {
+        return NULL;
     }
-
-    (*entity) = new;
-    return APR_SUCCESS;
+    return mm_calloc(shared->mm, 1, size);
 }
 
+/* ***APRDOC********************************************************
+ * ap_status_t ap_shm_free(ap_shmem_t *, void *)
+ *    free shared memory previously allocated.
+ * arg 1) The shared memory block to destroy. 
+ */
 ap_status_t ap_shm_free(struct shmem_t *shared, void *entity)
 {
     mm_free(shared->mm, entity);
     return APR_SUCCESS;
 }
 
-ap_status_t ap_shm_strdup(char **new, struct shmem_t *shared, const char *old)
+/* ***APRDOC********************************************************
+ * ap_status_t ap_get_shm_name(ap_shmem_t *, ap_shm_name_t **)
+ *    Get the name of the shared memory segment if not using
+ *    anonymous shared memory.
+ * arg 1)  The shared memory block to destroy. 
+ * arg 2)  The name of the shared memory block, NULL if anonymous 
+ *         shared memory.
+ * return) APR_USES_ANONYMOUS_SHM if we are using anonymous shared
+ *         memory.  APR_USES_FILEBASED_SHM if our shared memory is
+ *         based on file access.  APR_USES_KEYBASED_SHM if shared
+ *         memory is based on a key value such as shmctl.  If the
+ *         shared memory is anonymous, the name is NULL.
+ */
+ap_status_t ap_get_shm_name(ap_shmem_t *c, ap_shm_name_t **name)
 {
-    (*new) = mm_strdup(shared->mm, old);
-    if ((*new) == NULL) {
-        return APR_ENOMEM;
-    }
-    return APR_SUCCESS;
+#if APR_USES_ANONYMOUS_SHM
+    name = NULL;
+    return APR_ANONYMOUS;
+/* Currently, we are not supporting name based shared memory on Unix
+ * systems.  This may change in the future however, so I will leave
+ * this in here for now.  Plus, this gives other platforms a good idea
+ * of how to proceed.
+ */
+#elif APR_USES_FILEBASED_SHM
+#elif APR_USES_KEYBASED_SHM
+#endif
 }
 
-ap_status_t ap_shm_sizeof(struct shmem_t *shared, const void *ent, 
-                          ap_size_t *size)
+/* ***APRDOC********************************************************
+ * ap_status_t ap_set_shm_name(ap_shmem_t *, ap_shm_name_t *)
+ *    Set the name of the shared memory segment if not using
+ *    anonymous shared memory.  This is to allow processes to open
+ *    shared memory created by another process.
+ * arg 1)  The shared memory block to destroy. 
+ * arg 2)  The name of the shared memory block, NULL if anonymous 
+ *         shared memory.
+ * return) APR_USES_ANONYMOUS_SHM if we are using anonymous shared
+ *         memory.  APR_SUCCESS if we are using named shared memory
+ *         and we were able to assign the name correctly. 
+ */
+ap_status_t ap_set_shm_name(ap_shmem_t *c, ap_shm_name_t *name)
 {
-    *size = mm_sizeof(shared->mm, ent);
-    if ((*size) == -1) {
-        return APR_EINVAL;
-    }
-    return APR_SUCCESS;
+#if APR_USES_ANONYMOUS_SHM
+    return APR_ANONYMOUS;
+/* Currently, we are not supporting name based shared memory on Unix
+ * systems.  This may change in the future however, so I will leave
+ * this in here for now.  Plus, this gives other platforms a good idea
+ * of how to proceed.
+ */
+#elif APR_USES_FILEBASED_SHM
+#elif APR_USES_KEYBASED_SHM
+#endif
 }
 
-ap_status_t ap_shm_maxsize(ap_size_t *size)
+/* ***APRDOC********************************************************
+ * ap_status_t ap_open_shmem(ap_shmem_t *)
+ *    Open the shared memory block in a child process. 
+ * arg 1)  The shared memory block to open in the child. 
+ * return) This should be called after ap_set_shm_name.  The ap_shmem_t 
+ *         variable must refer to the memory segment to open.
+ */
+ap_status_t ap_open_shmem(struct shmem_t *c)
 {
-    (*size) = mm_maxsize();
-    if ((*size) <= 0) {
-        return APR_ENOMEM;
-    }
+#if APR_USES_ANONYMOUS_SHM
+/* When using MM, we don't need to open shared memory segments in child
+ * segments, so just return immediately.
+ */
     return APR_SUCCESS;
+/* Currently, we are not supporting name based shared memory on Unix
+ * systems.  This may change in the future however, so I will leave
+ * this in here for now.  Plus, this gives other platforms a good idea
+ * of how to proceed.
+ */
+#elif APR_USES_FILEBASED_SHM
+#elif APR_USES_KEYBASED_SHM
+#endif
 }
 
-ap_status_t ap_shm_available(struct shmem_t *shared, ap_size_t *size)
+/* ***APRDOC********************************************************
+ * ap_status_t ap_shm_avail(ap_shmem_t *, ap_size_t *)
+ *    Determine how much memory is available in the specified shared
+ *    memory block
+ * arg 1)  The shared memory block to open in the child. 
+ * arg 2)  The amount of space available in the shared memory block.
+ */
+ap_status_t ap_shm_avail(struct shmem_t *c, ap_size_t *size)
 {
-    (*size) = mm_available(shared->mm);
-    if ((*size) <= 0) {
-        return APR_ENOMEM;
+    *size = mm_available(c);
+    if (*size == 0) {
+        return APR_ESHMLOCK;
     }
     return APR_SUCCESS;
 }
-
-ap_status_t ap_shm_child_create(ap_context_t *cont, const char *fname, 
-                                struct shmem_t **shared)
-{
-    return APR_SUCCESS;
-}
-
-
diff --git a/test/Makefile.in b/test/Makefile.in
index 5f1eb34d9..312299483 100644
--- a/test/Makefile.in
+++ b/test/Makefile.in
@@ -22,7 +22,8 @@ TARGETS= testfile@EXEEXT@ \
 	testcontext@EXEEXT@ \
 	ab@EXEEXT@ \
 	htdigest@EXEEXT@ \
-	testmmap@EXEEXT@
+	testmmap@EXEEXT@ \
+	testshmem@EXEEXT@
 
 OBJS= testfile.o \
 	testproc.o \
@@ -72,6 +73,9 @@ testtime@EXEEXT@: testtime.o
 testmmap@EXEEXT@: testmmap.o
 	$(CC) $(CFLAGS) testmmap.o -o testmmap@EXEEXT@ $(LDFLAGS)
 
+testshmem@EXEEXT@: testshmem.o
+	$(CC) $(CFLAGS) testshmem.o -o testshmem@EXEEXT@ $(LDFLAGS)
+
 clean:
 	$(RM) -f *.o *.a *.so $(TARGETS)
 
diff --git a/shmem/shmem.c b/test/testshmem.c
index 41f56b84c..bde3bde86 100644
--- a/shmem/shmem.c
+++ b/test/testshmem.c
@@ -52,106 +52,90 @@
  * project, please see <http://www.apache.org/>.
  *
  */
+#include "apr_shmem.h"
+#include "apr_lock.h"
+#include "apr_errno.h"
+#include "apr_general.h"
+#include "apr_lib.h"
+#include "errno.h"
+#include <stdio.h>
+#ifdef BEOS
+#include <unistd.h>
+#endif
 
-struct shmem_t {
-    MM *mm;
-    ap_context_t *cntxt;
-}
+typedef struct mbox {
+    char msg[1024]; 
+    int msgavail; 
+} mbox;
+ap_context_t *context;
+mbox *boxes;
 
-ap_status_t ap_shm_create(struct shmem_t **new, ap_context_t *cont, ap_size_t size, const char *file)
+void msgwait(int boxnum)
 {
-    MM *mm = mm_create(size, file);
-
-    if (mm == NULL) {
-        return APR_ENOMEM;
-    }
-    (*new) = (struct shmem_t *)mm_malloc(mm, sizeof(struct shmem_t));
-    if ((*new) == NULL)
-        return APR_ENOMEM;
-    }
-    (*new)->mm = mm;
-    (*new)->cntxt = cont;
-    return APR_SUCCESS;
+    volatile int test = 0;
+    while (test == 0) {
+        test = boxes[boxnum].msgavail;
+    }    
+    fprintf(stdout, "\nreceived a message in box %d, message was: %s\n", 
+            boxnum, boxes[boxnum].msg); 
 }
 
-ap_status_t ap_shm_destroy(struct shmem_t *shared)
+void msgput(int boxnum, char *msg)
 {
-    mm_destroy(shared->mm);
-    shared->mm = NULL;
-    return APR_SUCCESS;
+    fprintf(stdout, "Sending message to box %d\n", boxnum);
+    ap_cpystrn(boxes[boxnum].msg, msg, strlen(msg));
+    boxes[boxnum].msgavail = 1;
 }
 
-ap_status_t ap_shm_malloc(void **entity, struct shmem_t *shared, ap_size_t size)
+int main()
 {
-    entity = mm_malloc(shared->mm, size);
-    if (entity == NULL) {
-        return APR_ENOMEM;
-    }
-    return APR_SUCCESS;
-}
+    ap_status_t s4;
+    ap_shmem_t *shm;
+    pid_t pid;
+    ap_status_t s1;
+    int size;
 
-ap_status_t ap_shm_calloc(void **entity, struct shmem_t *shared, ap_size_t size)
-{
-    entity = mm_calloc(shared->mm, size);
-    if (entity == NULL) {
-        return APR_ENOMEM;
-    }
-    return APR_SUCCESS;
-}
-
-ap_status_t ap_shm_realloc(void **entity, struct shmem_t *shared, ap_size_t size)
-{
-    void *new;
+    ap_initialize();
 
-    new = mm_realloc(shared->mm, *entity, size);
-    if (new == NULL)
-        return APR_ENOMEM;
+    fprintf(stdout, "Initializing the context......."); 
+    if (ap_create_context(&context, NULL) != APR_SUCCESS) {
+        fprintf(stderr, "could not initialize\n");
+        exit(-1);
     }
+    fprintf(stdout, "OK\n");
 
-    (*entity) = new;
-    return APR_SUCCESS;
-}
-
-ap_status_t ap_shm_free(struct shmem_t *shared, void *entity)
-{
-    mm_free(shared->mm, entity);
-    return APR_SUCCESS;
-}
-
-ap_status_t ap_shm_strdup(char **new, struct shmem_t *shared, const char *old)
-{
-    (*new) = mm_strdup(shared->mm, old);
-    if ((*new) == NULL) {
-        return APR_ENOMEM;
+    fprintf(stdout, "Creating shared memory block......."); 
+    if (ap_shm_init(&shm, 1048576, NULL) != APR_SUCCESS) { 
+        fprintf(stderr, "Error allocating shared memory block\n");
+        exit(-1);
     }
-    return APR_SUCCESS;
-}
+    fprintf(stdout, "OK\n");
 
-ap_status_t ap_shm_sizeof(struct shmem_t *shared, const void *ent, 
-                          ap_size_t *size)
-{
-    *size = mm_sizeof(shared->mm, ent);
-    if ((*size) == -1) {
-        return APR_EINVAL;
+    fprintf(stdout, "Allocating shared memory......."); 
+    size = sizeof(mbox) * 2;
+    boxes = ap_shm_calloc(shm, size);
+    if (boxes == NULL) { 
+        fprintf(stderr, "Error creating message boxes.\n");
+        exit(-1);
     }
-    return APR_SUCCESS;
-}
+    fprintf(stdout, "OK\n");
 
-ap_status_t ap_shm_maxsize(ap_size_t **size)
-{
-    (*size) = mm_maxsize();
-    if ((*size) <= 0) {
-        return APR_ENOMEM;
+    fprintf(stdout, "Creating a child process\n");
+    pid = fork();
+    if (pid == 0) {
+sleep(1);
+        msgwait(1);
+        msgput(0, "Msg received\n");
+        exit(1);
     }
-    return APR_SUCCESS;
-}
-
-ap_status_t ap_shm_available(struct shmem_t *shared, ap_size_t *size)
-{
-    (*size) = mm_available(shared->mm);
-    if ((*size <= 0) {
-        return APR_ENOMEM;
+    else if (pid > 0) {
+        msgput(1, "Sending a message\n");
+sleep(1);
+        msgwait(0);
+        exit(1);
+    }
+    else {
+        fprintf(stderr, "Error creating a child process\n");
+        exit(1);
     }
-    return APR_SUCCESS;
 }
-