kernel/syscalls: Implement sys_tell & sys_seek

Signed-off-by: EnderIce2 <enderice2@protonmail.com>
This commit is contained in:
EnderIce2 2024-12-26 03:20:27 +02:00
parent b208862de2
commit 1695418dcb
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2 changed files with 71 additions and 0 deletions

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@ -232,6 +232,13 @@ typedef enum
__SYS_SET_FS = 3, __SYS_SET_FS = 3,
} prctl_options_t; } prctl_options_t;
typedef enum
{
__SYS_SEEK_SET = 0,
__SYS_SEEK_CUR = 1,
__SYS_SEEK_END = 2
} seek_whence_t;
typedef enum typedef enum
{ {
__SYS_SIGNULL = 0, __SYS_SIGNULL = 0,
@ -685,6 +692,46 @@ typedef enum
* - #EINVAL if `length` is invalid * - #EINVAL if `length` is invalid
*/ */
SYS_FTRUNCATE, SYS_FTRUNCATE,
/**
* @brief Get the current file offset
*
* @code
* off_t tell(int fd);
* @endcode
*
* @details Returns the current file offset for the file referred to by `fd`.
*
* @param fd File descriptor
*
* @return
* - Current file offset on success
* - #EBADF if `fd` is not a valid file descriptor
*/
SYS_TELL,
/**
* @brief Set the file offset
*
* @code
* off_t seek(int fd, off_t offset, int whence);
* @endcode
*
* @details Sets the file offset for the file referred to by `fd` to the
* specified `offset` according to the directive `whence`.
*
* @param fd File descriptor
* @param offset Offset to set
* @param whence Directive for setting the offset\n
* Supported values:
* - #__SYS_SEEK_SET: Set the offset to `offset` bytes
* - #__SYS_SEEK_CUR: Set the offset to the current offset plus `offset`
* - #__SYS_SEEK_END: Set the offset to the size of the file plus `offset`
*
* @return
* - New file offset on success
* - #EBADF if `fd` is not a valid file descriptor
* - #EINVAL if `whence` is invalid
*/
SYS_SEEK,
/* Process Control */ /* Process Control */
@ -1376,6 +1423,12 @@ typedef enum
/** @copydoc SYS_FTRUNCATE */ /** @copydoc SYS_FTRUNCATE */
#define call_ftruncate(fd, length) syscall2(SYS_FTRUNCATE, (scarg)fd, (scarg)length) #define call_ftruncate(fd, length) syscall2(SYS_FTRUNCATE, (scarg)fd, (scarg)length)
/** @copydoc SYS_TELL */
#define call_tell(fd) syscall1(SYS_TELL, (scarg)fd)
/** @copydoc SYS_SEEK */
#define call_seek(fd, offset, whence) syscall3(SYS_SEEK, (scarg)fd, (scarg)offset, (scarg)whence)
/* Process Control */ /* Process Control */
/** @copydoc SYS_EXIT */ /** @copydoc SYS_EXIT */

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@ -159,6 +159,22 @@ static int sys_access(SysFrm *Frame, const char *pathname, int mode)
static int sys_truncate(SysFrm *Frame, const char *pathname, off_t length) { return -ENOSYS; } static int sys_truncate(SysFrm *Frame, const char *pathname, off_t length) { return -ENOSYS; }
static int sys_ftruncate(SysFrm *Frame, int fd, off_t length) { return -ENOSYS; } static int sys_ftruncate(SysFrm *Frame, int fd, off_t length) { return -ENOSYS; }
static int sys_tell(SysFrm *Frame, int fd)
{
PCB *pcb = thisProcess;
vfs::FileDescriptorTable *fdt = pcb->FileDescriptors;
return fdt->usr_lseek(fd, 0, SEEK_CUR);
}
static off_t sys_seek(SysFrm *Frame, int fd, off_t offset, int whence)
{
PCB *pcb = thisProcess;
vfs::FileDescriptorTable *fdt = pcb->FileDescriptors;
return fdt->usr_lseek(fd, offset, whence);
}
static __noreturn void sys_exit(SysFrm *Frame, int status) static __noreturn void sys_exit(SysFrm *Frame, int status)
{ {
TCB *t = thisThread; TCB *t = thisThread;
@ -333,6 +349,8 @@ __constructor void __init_native_syscalls(void)
scTbl[SYS_ACCESS] = {"SYS_ACCESS", (void *)sys_access}; scTbl[SYS_ACCESS] = {"SYS_ACCESS", (void *)sys_access};
scTbl[SYS_TRUNCATE] = {"SYS_TRUNCATE", (void *)sys_truncate}; scTbl[SYS_TRUNCATE] = {"SYS_TRUNCATE", (void *)sys_truncate};
scTbl[SYS_FTRUNCATE] = {"SYS_FTRUNCATE", (void *)sys_ftruncate}; scTbl[SYS_FTRUNCATE] = {"SYS_FTRUNCATE", (void *)sys_ftruncate};
scTbl[SYS_TELL] = {"SYS_TELL", (void *)sys_tell};
scTbl[SYS_SEEK] = {"SYS_SEEK", (void *)sys_seek};
/* Process Control */ /* Process Control */
scTbl[SYS_EXIT] = {"SYS_EXIT", (void *)sys_exit}; scTbl[SYS_EXIT] = {"SYS_EXIT", (void *)sys_exit};