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#include <assert.h>
#include <errno.h>
#include <fs/shm.h>
#include <fs/vfs.h>
#include <hashmap/hashmap.h>
#include <mmu.h>
#include <sched/scheduler.h>
#include <stddef.h>
HashMap *shared_memory_objects;
void shm_init(void) { shared_memory_objects = hashmap_create(10); }
int shm_write(uint8_t *buffer, uint64_t offset, uint64_t len, vfs_fd_t *fd) {
vfs_vm_object_t *p = fd->inode->internal_object;
if (offset > p->size)
return -EFBIG;
if (offset + len > p->size)
len = p->size - offset;
memcpy((void *)((uintptr_t)((uintptr_t)p->virtual_object + offset)), buffer,
len);
return len;
}
int shm_read(uint8_t *buffer, uint64_t offset, uint64_t len, vfs_fd_t *fd) {
vfs_vm_object_t *p = fd->inode->internal_object;
if (offset > p->size)
return -EFBIG;
if (offset + len > p->size)
len = p->size - offset;
memcpy((void *)buffer,
(void *)((uintptr_t)((uintptr_t)p->virtual_object + offset)), len);
return len;
}
vfs_vm_object_t *shm_get_vm_object(uint64_t length, uint64_t offset,
vfs_fd_t *fd) {
(void)length;
(void)offset;
vfs_vm_object_t *p = fd->inode->internal_object;
return p;
}
int shm_ftruncate(vfs_fd_t *fd, size_t length) {
vfs_vm_object_t *p = fd->inode->internal_object;
p->size = length;
p->virtual_object = ksbrk(length);
int n = (uintptr_t)align_page((void *)(uint32_t)length) / 0x1000;
p->object = kmalloc(sizeof(void *) * n);
for (int i = 0; i < n; i++)
p->object[i] =
(void *)(get_page(p->virtual_object + (i * 0x1000), NULL, 0, 0)->frame *
0x1000);
return 0;
}
int shm_open(const char *name, int oflag, mode_t mode) {
// Try to find or create a new shared memory object.
vfs_vm_object_t *internal_object =
hashmap_get_entry(shared_memory_objects, name);
if (!internal_object) {
// if (!(oflag & O_CREAT))
// return -EMFILE;
internal_object = kmalloc(sizeof(vfs_vm_object_t));
internal_object->object = NULL;
internal_object->size = 0;
hashmap_add_entry(shared_memory_objects, name, internal_object, NULL, 0);
}
vfs_inode_t *inode = vfs_create_inode(
0 /*inode_num*/, 0 /*type*/, 1 /*has_data*/, 1 /*can_write*/,
1 /*is_open*/, internal_object, 0 /*file_size*/, NULL /*open*/,
NULL /*create_file*/, shm_read, shm_write, NULL /*close*/,
NULL /*create_directory*/, shm_get_vm_object, shm_ftruncate);
vfs_fd_t *fd_ptr;
int fd = vfs_create_fd(oflag, mode, inode, &fd_ptr);
if (-1 == fd) {
kfree(inode);
return -EMFILE;
}
return fd;
}
int shm_unlink(const char *name) {
(void)name;
return 0;
}
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