u-boot/include/os.h
Simon Glass 4af3e9ad8a sandbox: Restore blocking I/O on exit
At present sandbox sets non-blocking I/O as soon as any input is read
from the terminal. However it does not restore the previous state on
exit. Fix this and drop the old os_read_no_block() function.

This means that we always enable blocking I/O in sandbox (if input is a
terminal) whereas previously it would only happen on the first call to
tstc() or getc(). However, the difference is likely not important.

Signed-off-by: Simon Glass <sjg@chromium.org>
2018-10-09 04:40:27 -06:00

354 lines
9.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Operating System Interface
*
* This provides access to useful OS routines for the sandbox architecture.
* They are kept in a separate file so we can include system headers.
*
* Copyright (c) 2011 The Chromium OS Authors.
*/
#ifndef __OS_H__
#define __OS_H__
#include <linux/types.h>
struct rtc_time;
struct sandbox_state;
/**
* Access to the OS read() system call
*
* \param fd File descriptor as returned by os_open()
* \param buf Buffer to place data
* \param count Number of bytes to read
* \return number of bytes read, or -1 on error
*/
ssize_t os_read(int fd, void *buf, size_t count);
/**
* Access to the OS write() system call
*
* \param fd File descriptor as returned by os_open()
* \param buf Buffer containing data to write
* \param count Number of bytes to write
* \return number of bytes written, or -1 on error
*/
ssize_t os_write(int fd, const void *buf, size_t count);
/**
* Access to the OS lseek() system call
*
* \param fd File descriptor as returned by os_open()
* \param offset File offset (based on whence)
* \param whence Position offset is relative to (see below)
* \return new file offset
*/
off_t os_lseek(int fd, off_t offset, int whence);
/* Defines for "whence" in os_lseek() */
#define OS_SEEK_SET 0
#define OS_SEEK_CUR 1
#define OS_SEEK_END 2
/**
* Access to the OS open() system call
*
* \param pathname Pathname of file to open
* \param flags Flags, like OS_O_RDONLY, OS_O_RDWR
* \return file descriptor, or -1 on error
*/
int os_open(const char *pathname, int flags);
#define OS_O_RDONLY 0
#define OS_O_WRONLY 1
#define OS_O_RDWR 2
#define OS_O_MASK 3 /* Mask for read/write flags */
#define OS_O_CREAT 0100
#define OS_O_TRUNC 01000
/**
* Access to the OS close() system call
*
* \param fd File descriptor to close
* \return 0 on success, -1 on error
*/
int os_close(int fd);
/**
* Access to the OS unlink() system call
*
* \param pathname Path of file to delete
* \return 0 for success, other for error
*/
int os_unlink(const char *pathname);
/**
* Access to the OS exit() system call
*
* This exits with the supplied return code, which should be 0 to indicate
* success.
*
* @param exit_code exit code for U-Boot
*/
void os_exit(int exit_code) __attribute__((noreturn));
/**
* Put tty into raw mode to mimic serial console better
*
* @param fd File descriptor of stdin (normally 0)
* @param allow_sigs Allow Ctrl-C, Ctrl-Z to generate signals rather than
* be handled by U-Boot
*/
void os_tty_raw(int fd, bool allow_sigs);
/**
* Restore the tty to its original mode
*
* Call this to restore the original terminal mode, after it has been changed
* by os_tty_raw(). This is an internal function.
*/
void os_fd_restore(void);
/**
* Acquires some memory from the underlying os.
*
* \param length Number of bytes to be allocated
* \return Pointer to length bytes or NULL on error
*/
void *os_malloc(size_t length);
/**
* Free memory previous allocated with os_malloc()/os_realloc()
*
* This returns the memory to the OS.
*
* \param ptr Pointer to memory block to free
*/
void os_free(void *ptr);
/**
* Reallocate previously-allocated memory to increase/decrease space
*
* This works in a similar way to the C library realloc() function. If
* length is 0, then ptr is freed. Otherwise the space used by ptr is
* expanded or reduced depending on whether length is larger or smaller
* than before.
*
* If ptr is NULL, then this is similar to calling os_malloc().
*
* This function may need to move the memory block to make room for any
* extra space, in which case the new pointer is returned.
*
* \param ptr Pointer to memory block to reallocate
* \param length New length for memory block
* \return pointer to new memory block, or NULL on failure or if length
* is 0.
*/
void *os_realloc(void *ptr, size_t length);
/**
* Access to the usleep function of the os
*
* \param usec Time to sleep in micro seconds
*/
void os_usleep(unsigned long usec);
/**
* Gets a monotonic increasing number of nano seconds from the OS
*
* \return A monotonic increasing time scaled in nano seconds
*/
uint64_t os_get_nsec(void);
/**
* Parse arguments and update sandbox state.
*
* @param state Sandbox state to update
* @param argc Argument count
* @param argv Argument vector
* @return 0 if ok, and program should continue;
* 1 if ok, but program should stop;
* -1 on error: program should terminate.
*/
int os_parse_args(struct sandbox_state *state, int argc, char *argv[]);
/*
* Types of directory entry that we support. See also os_dirent_typename in
* the C file.
*/
enum os_dirent_t {
OS_FILET_REG, /* Regular file */
OS_FILET_LNK, /* Symbolic link */
OS_FILET_DIR, /* Directory */
OS_FILET_UNKNOWN, /* Something else */
OS_FILET_COUNT,
};
/** A directory entry node, containing information about a single dirent */
struct os_dirent_node {
struct os_dirent_node *next; /* Pointer to next node, or NULL */
ulong size; /* Size of file in bytes */
enum os_dirent_t type; /* Type of entry */
char name[0]; /* Name of entry */
};
/**
* Get a directionry listing
*
* This allocates and returns a linked list containing the directory listing.
*
* @param dirname Directory to examine
* @param headp Returns pointer to head of linked list, or NULL if none
* @return 0 if ok, -ve on error
*/
int os_dirent_ls(const char *dirname, struct os_dirent_node **headp);
/**
* Free directory list
*
* This frees a linked list containing a directory listing.
*
* @param node Pointer to head of linked list
*/
void os_dirent_free(struct os_dirent_node *node);
/**
* Get the name of a directory entry type
*
* @param type Type to check
* @return string containing the name of that type, or "???" if none/invalid
*/
const char *os_dirent_get_typename(enum os_dirent_t type);
/**
* Get the size of a file
*
* @param fname Filename to check
* @param size size of file is returned if no error
* @return 0 on success or -1 if an error ocurred
*/
int os_get_filesize(const char *fname, loff_t *size);
/**
* Write a character to the controlling OS terminal
*
* This bypasses the U-Boot console support and writes directly to the OS
* stdout file descriptor.
*
* @param ch Character to write
*/
void os_putc(int ch);
/**
* Write a string to the controlling OS terminal
*
* This bypasses the U-Boot console support and writes directly to the OS
* stdout file descriptor.
*
* @param str String to write (note that \n is not appended)
*/
void os_puts(const char *str);
/**
* Write the sandbox RAM buffer to a existing file
*
* @param fname Filename to write memory to (simple binary format)
* @return 0 if OK, -ve on error
*/
int os_write_ram_buf(const char *fname);
/**
* Read the sandbox RAM buffer from an existing file
*
* @param fname Filename containing memory (simple binary format)
* @return 0 if OK, -ve on error
*/
int os_read_ram_buf(const char *fname);
/**
* Jump to a new executable image
*
* This uses exec() to run a new executable image, after putting it in a
* temporary file. The same arguments and environment are passed to this
* new image, with the addition of:
*
* -j <filename> Specifies the filename the image was written to. The
* calling image may want to delete this at some point.
* -m <filename> Specifies the file containing the sandbox memory
* (ram_buf) from this image, so that the new image can
* have access to this. It also means that the original
* memory filename passed to U-Boot will be left intact.
*
* @param dest Buffer containing executable image
* @param size Size of buffer
*/
int os_jump_to_image(const void *dest, int size);
/**
* os_find_u_boot() - Determine the path to U-Boot proper
*
* This function is intended to be called from within sandbox SPL. It uses
* a few heuristics to find U-Boot proper. Normally it is either in the same
* directory, or the directory above (since u-boot-spl is normally in an
* spl/ subdirectory when built).
*
* @fname: Place to put full path to U-Boot
* @maxlen: Maximum size of @fname
* @return 0 if OK, -NOSPC if the filename is too large, -ENOENT if not found
*/
int os_find_u_boot(char *fname, int maxlen);
/**
* os_spl_to_uboot() - Run U-Boot proper
*
* When called from SPL, this runs U-Boot proper. The filename is obtained by
* calling os_find_u_boot().
*
* @fname: Full pathname to U-Boot executable
* @return 0 if OK, -ve on error
*/
int os_spl_to_uboot(const char *fname);
/**
* Read the current system time
*
* This reads the current Local Time and places it into the provided
* structure.
*
* @param rt Place to put system time
*/
void os_localtime(struct rtc_time *rt);
/**
* os_abort() - Raise SIGABRT to exit sandbox (e.g. to debugger)
*/
void os_abort(void);
/**
* os_mprotect_allow() - Remove write-protection on a region of memory
*
* The start and length will be page-aligned before use.
*
* @start: Region start
* @len: Region length in bytes
* @return 0 if OK, -1 on error from mprotect()
*/
int os_mprotect_allow(void *start, size_t len);
/**
* os_write_file() - Write a file to the host filesystem
*
* This can be useful when debugging for writing data out of sandbox for
* inspection by external tools.
*
* @name: File path to write to
* @buf: Data to write
* @size: Size of data to write
* @return 0 if OK, -ve on error
*/
int os_write_file(const char *name, const void *buf, int size);
#endif