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-rw-r--r--source3/locking/shmem_sysv.c304
1 files changed, 152 insertions, 152 deletions
diff --git a/source3/locking/shmem_sysv.c b/source3/locking/shmem_sysv.c
index 8832902820..14ed199738 100644
--- a/source3/locking/shmem_sysv.c
+++ b/source3/locking/shmem_sysv.c
@@ -2,7 +2,7 @@
Unix SMB/Netbios implementation.
Version 1.9.
Shared memory functions - SYSV IPC implementation
- Copyright (C) Erik Devriendt 1996-1997
+ Copyright (C) Andrew Tridgell 1997
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@@ -53,7 +53,7 @@ extern int DEBUGLEVEL;
#define SHMEM_HASH_SIZE 63
#endif
-#define MIN_SHM_SIZE 10240
+#define MIN_SHM_SIZE 0x1000
static int shm_id;
static int sem_id;
@@ -83,19 +83,18 @@ struct ShmBlockDesc
{
int next; /* offset of next block in the free list or
SHM_NOT_FREE_OFF when block in use */
- int size; /* user size in BlockDescSize units */
+ int size; /* user size in BlockDescSize units */
};
-#define EOList_Addr (struct ShmBlockDesc *)( 0 )
-#define EOList_Off (NULL_OFFSET)
+#define EOList_Addr NULL
+#define EOList_Off (0)
#define CellSize sizeof(struct ShmBlockDesc)
-/* HeaderSize aligned on 8 byte boundary */
-#define AlignedHeaderSize ((sizeof(struct ShmHeader)+7) & ~7)
-
-static struct ShmHeader *shm_header_p = (struct ShmHeader *)0;
+/* HeaderSize aligned on a 8 byte boundary */
+#define AlignedHeaderSize ((sizeof(struct ShmHeader)+7) & ~7)
+static struct ShmHeader *shm_header_p = NULL;
static BOOL shm_initialize_called = False;
static int read_only;
@@ -156,22 +155,22 @@ static BOOL global_unlock(void)
static void *shm_offset2addr(int offset)
{
- if (offset == NULL_OFFSET )
+ if (offset == 0 )
return (void *)(0);
if (!shm_header_p)
return (void *)(0);
- return (void *)((char *)shm_header_p + offset );
+ return (void *)((char *)shm_header_p + offset);
}
static int shm_addr2offset(void *addr)
{
if (!addr)
- return NULL_OFFSET;
+ return 0;
if (!shm_header_p)
- return NULL_OFFSET;
+ return 0;
return (int)((char *)addr - (char *)shm_header_p);
}
@@ -189,7 +188,7 @@ static int shm_alloc(int size)
if (!shm_header_p) {
/* not mapped yet */
DEBUG(0,("ERROR shm_alloc : shmem not mapped\n"));
- return NULL_OFFSET;
+ return 0;
}
global_lock();
@@ -197,13 +196,13 @@ static int shm_alloc(int size)
if (!shm_header_p->consistent) {
DEBUG(0,("ERROR shm_alloc : shmem not consistent\n"));
global_unlock();
- return NULL_OFFSET;
+ return 0;
}
- /* calculate the number of cells */
- num_cells = (size + CellSize -1) / CellSize;
+ /* calculate the number of cells */
+ num_cells = (size + (CellSize-1)) / CellSize;
- /* set start of scan */
+ /* set start of scan */
prev_p = (struct ShmBlockDesc *)shm_offset2addr(shm_header_p->first_free_off);
scanner_p = prev_p ;
@@ -216,144 +215,50 @@ static int shm_alloc(int size)
/* at this point scanner point to a block header or to the end of
the list */
if (scanner_p == EOList_Addr) {
- DEBUG(0,("ERROR shm_alloc : alloc of %d bytes failed, no free space found\n",size));
+ DEBUG(0,("ERROR shm_alloc : alloc of %d bytes failed\n",size));
global_unlock();
- return (NULL_OFFSET);
+ return (0);
}
/* going to modify shared mem */
shm_header_p->consistent = False;
/* if we found a good one : scanner == the good one */
- if (scanner_p->size <= num_cells + 2) {
- /* there is no use in making a new one, it will be too small anyway
- * we will link out scanner
- */
- if ( prev_p == scanner_p ) {
- shm_header_p->first_free_off = scanner_p->next ;
- } else {
- prev_p->next = scanner_p->next ;
- }
- shm_header_p->statistics.cells_free -= scanner_p->size;
- shm_header_p->statistics.cells_used += scanner_p->size;
- } else {
+ if (scanner_p->size > num_cells + 2) {
/* Make a new one */
new_p = scanner_p + 1 + num_cells;
- new_p->size = scanner_p->size - num_cells - 1;
+ new_p->size = scanner_p->size - (num_cells + 1);
new_p->next = scanner_p->next;
scanner_p->size = num_cells;
scanner_p->next = shm_addr2offset(new_p);
-
- if (prev_p != scanner_p) {
- prev_p->next = shm_addr2offset(new_p) ;
- } else {
- shm_header_p->first_free_off = shm_addr2offset(new_p);
- }
- shm_header_p->statistics.cells_free -= num_cells+1;
- shm_header_p->statistics.cells_used += num_cells;
+
+ shm_header_p->statistics.cells_free -= 1;
shm_header_p->statistics.cells_system += 1;
}
- result_offset = shm_addr2offset( &(scanner_p[1]) );
- scanner_p->next = SHM_NOT_FREE_OFF ;
+ /* take it from the free list */
+ if (prev_p == scanner_p) {
+ shm_header_p->first_free_off = scanner_p->next;
+ } else {
+ prev_p->next = scanner_p->next;
+ }
+ shm_header_p->statistics.cells_free -= scanner_p->size;
+ shm_header_p->statistics.cells_used += scanner_p->size;
+
+ result_offset = shm_addr2offset(&(scanner_p[1]));
+ scanner_p->next = SHM_NOT_FREE_OFF;
/* end modification of shared mem */
shm_header_p->consistent = True;
-
- DEBUG(6,("shm_alloc : request for %d bytes, allocated %d bytes at offset %d\n",size,scanner_p->size*CellSize,result_offset ));
global_unlock();
+
+ DEBUG(6,("shm_alloc : allocated %d bytes at offset %d\n",
+ size,result_offset));
+
return result_offset;
}
-
-
-/*
- * Function to create the hash table for the share mode entries. Called
- * when smb shared memory is global locked.
- */
-static BOOL shm_create_hash_table( unsigned int size )
-{
- size *= sizeof(int);
-
- global_lock();
- shm_header_p->userdef_off = shm_alloc( size );
-
- if(shm_header_p->userdef_off == NULL_OFFSET) {
- DEBUG(0,("shm_create_hash_table: Failed to create hash table of size %d\n",size));
- global_unlock();
- return False;
- }
-
- /* Clear hash buckets. */
- memset( shm_offset2addr(shm_header_p->userdef_off), '\0', size);
- global_unlock();
- return True;
-}
-
-static BOOL shm_validate_header(int size)
-{
- if( !shm_header_p ) {
- /* not mapped yet */
- DEBUG(0,("ERROR shm_validate_header : shmem not mapped\n"));
- return False;
- }
-
- if(shm_header_p->shm_magic != SHM_MAGIC) {
- DEBUG(0,("ERROR shm_validate_header : bad magic\n"));
- return False;
- }
-
- if(shm_header_p->shm_version != SHM_VERSION) {
- DEBUG(0,("ERROR shm_validate_header : bad version %X\n",shm_header_p->shm_version));
- return False;
- }
-
- if(shm_header_p->total_size != size) {
- DEBUG(0,("ERROR shm_validate_header : shmem size mismatch (old = %d, new = %d)\n",shm_header_p->total_size,size));
- return False;
- }
-
- if(!shm_header_p->consistent) {
- DEBUG(0,("ERROR shm_validate_header : shmem not consistent\n"));
- return False;
- }
- return True;
-}
-
-static BOOL shm_initialize(int size)
-{
- struct ShmBlockDesc * first_free_block_p;
-
- DEBUG(5,("shm_initialize : initializing shmem file of size %d\n",size));
-
- if( !shm_header_p ) {
- /* not mapped yet */
- DEBUG(0,("ERROR shm_initialize : shmem not mapped\n"));
- return False;
- }
-
- shm_header_p->shm_magic = SHM_MAGIC;
- shm_header_p->shm_version = SHM_VERSION;
- shm_header_p->total_size = size;
- shm_header_p->first_free_off = AlignedHeaderSize;
- shm_header_p->userdef_off = NULL_OFFSET;
-
- first_free_block_p = (struct ShmBlockDesc *)shm_offset2addr(shm_header_p->first_free_off);
- first_free_block_p->next = EOList_Off;
- first_free_block_p->size = ( size - AlignedHeaderSize - CellSize ) / CellSize ;
-
- shm_header_p->statistics.cells_free = first_free_block_p->size;
- shm_header_p->statistics.cells_used = 0;
- shm_header_p->statistics.cells_system = 1;
-
- shm_header_p->consistent = True;
-
- shm_initialize_called = True;
-
- return True;
-}
-
static void shm_solve_neighbors(struct ShmBlockDesc *head_p )
{
struct ShmBlockDesc *next_p;
@@ -364,9 +269,9 @@ static void shm_solve_neighbors(struct ShmBlockDesc *head_p )
if ( head_p->next == EOList_Off ) return ;
next_p = (struct ShmBlockDesc *)shm_offset2addr(head_p->next);
- if ( ( head_p + head_p->size + 1 ) == next_p) {
- head_p->size += next_p->size +1 ; /* adapt size */
- head_p->next = next_p->next ; /* link out */
+ if ((head_p + head_p->size + 1) == next_p) {
+ head_p->size += next_p->size + 1; /* adapt size */
+ head_p->next = next_p->next; /* link out */
shm_header_p->statistics.cells_free += 1;
shm_header_p->statistics.cells_system -= 1;
@@ -374,21 +279,13 @@ static void shm_solve_neighbors(struct ShmBlockDesc *head_p )
}
-
-
-static BOOL shm_close( void )
-{
- return True;
-}
-
-
static BOOL shm_free(int offset)
{
struct ShmBlockDesc *header_p; /* pointer to header of
- block to free */
+ block to free */
struct ShmBlockDesc *scanner_p; /* used to scan the list */
struct ShmBlockDesc *prev_p; /* holds previous in the
- list */
+ list */
if (!shm_header_p) {
/* not mapped yet */
@@ -416,14 +313,16 @@ static BOOL shm_free(int offset)
/* find a place in the free_list to put the header in */
/* set scanner and previous pointer to start of list */
- prev_p = (struct ShmBlockDesc *)shm_offset2addr(shm_header_p->first_free_off);
+ prev_p = (struct ShmBlockDesc *)
+ shm_offset2addr(shm_header_p->first_free_off);
scanner_p = prev_p ;
while ((scanner_p != EOList_Addr) &&
(scanner_p < header_p)) {
/* while we didn't scan past its position */
prev_p = scanner_p ;
- scanner_p = (struct ShmBlockDesc *)shm_offset2addr(scanner_p->next);
+ scanner_p = (struct ShmBlockDesc *)
+ shm_offset2addr(scanner_p->next);
}
shm_header_p->consistent = False;
@@ -436,11 +335,12 @@ static BOOL shm_free(int offset)
shm_header_p->statistics.cells_used -= header_p->size;
/* we must free it at the beginning of the list */
- shm_header_p->first_free_off = shm_addr2offset(header_p); /* set the free_list_pointer to this block_header */
+ shm_header_p->first_free_off = shm_addr2offset(header_p);
+ /* set the free_list_pointer to this block_header */
/* scanner is the one that was first in the list */
header_p->next = shm_addr2offset(scanner_p);
- shm_solve_neighbors( header_p ); /* if neighbors then link them */
+ shm_solve_neighbors(header_p);
shm_header_p->consistent = True;
} else {
@@ -460,14 +360,113 @@ static BOOL shm_free(int offset)
}
+/*
+ * Function to create the hash table for the share mode entries. Called
+ * when smb shared memory is global locked.
+ */
+static BOOL shm_create_hash_table(unsigned int hash_entries)
+{
+ int size = hash_entries * sizeof(int);
+
+ global_lock();
+ shm_header_p->userdef_off = shm_alloc(size);
+
+ if(shm_header_p->userdef_off == 0) {
+ DEBUG(0,("shm_create_hash_table: Failed to create hash table of size %d\n",
+ size));
+ global_unlock();
+ return False;
+ }
+
+ /* Clear hash buckets. */
+ memset(shm_offset2addr(shm_header_p->userdef_off), '\0', size);
+ global_unlock();
+ return True;
+}
+
+
+static BOOL shm_validate_header(int size)
+{
+ if(!shm_header_p) {
+ /* not mapped yet */
+ DEBUG(0,("ERROR shm_validate_header : shmem not mapped\n"));
+ return False;
+ }
+
+ if(shm_header_p->shm_magic != SHM_MAGIC) {
+ DEBUG(0,("ERROR shm_validate_header : bad magic\n"));
+ return False;
+ }
+
+ if(shm_header_p->shm_version != SHM_VERSION) {
+ DEBUG(0,("ERROR shm_validate_header : bad version %X\n",
+ shm_header_p->shm_version));
+ return False;
+ }
+
+ if(shm_header_p->total_size != size) {
+ DEBUG(0,("ERROR shmem size mismatch (old = %d, new = %d)\n",
+ shm_header_p->total_size,size));
+ return False;
+ }
+
+ if(!shm_header_p->consistent) {
+ DEBUG(0,("ERROR shmem not consistent\n"));
+ return False;
+ }
+ return True;
+}
+
+
+static BOOL shm_initialize(int size)
+{
+ struct ShmBlockDesc * first_free_block_p;
+
+ DEBUG(5,("shm_initialize : initializing shmem size %d\n",size));
+
+ if( !shm_header_p ) {
+ /* not mapped yet */
+ DEBUG(0,("ERROR shm_initialize : shmem not mapped\n"));
+ return False;
+ }
+
+ shm_header_p->shm_magic = SHM_MAGIC;
+ shm_header_p->shm_version = SHM_VERSION;
+ shm_header_p->total_size = size;
+ shm_header_p->first_free_off = AlignedHeaderSize;
+ shm_header_p->userdef_off = 0;
+
+ first_free_block_p = (struct ShmBlockDesc *)
+ shm_offset2addr(shm_header_p->first_free_off);
+ first_free_block_p->next = EOList_Off;
+ first_free_block_p->size =
+ (size - (AlignedHeaderSize+CellSize))/CellSize;
+ shm_header_p->statistics.cells_free = first_free_block_p->size;
+ shm_header_p->statistics.cells_used = 0;
+ shm_header_p->statistics.cells_system = 1;
+
+ shm_header_p->consistent = True;
+
+ shm_initialize_called = True;
+
+ return True;
+}
+
+static BOOL shm_close( void )
+{
+ return True;
+}
+
+
static int shm_get_userdef_off(void)
{
if (!shm_header_p)
- return NULL_OFFSET;
+ return 0;
else
return shm_header_p->userdef_off;
}
+
/*******************************************************************
Lock a particular hash bucket entry.
******************************************************************/
@@ -500,7 +499,8 @@ static BOOL shm_get_usage(int *bytes_free,
*bytes_free = shm_header_p->statistics.cells_free * CellSize;
*bytes_used = shm_header_p->statistics.cells_used * CellSize;
- *bytes_overhead = shm_header_p->statistics.cells_system * CellSize + AlignedHeaderSize;
+ *bytes_overhead = shm_header_p->statistics.cells_system * CellSize +
+ AlignedHeaderSize;
return True;
}