Make stdin/stdout/stderr be FileHandles

Rework so that everything is a FileHandle, including
stdin/stdout/stderr.

Provide legacy functionality of calling serial_getc and serial_putc as
an internal "DirectSerial" FileHandle.

Add a JSON option to use UARTSerial instead.

Add hooks for target and application to provide custom FileHandles.

Allow for CRLF conversion to work on any FileHandle that isatty(),
as stdin/stdout or any other FILE. Optimise the conversion so it
doesn't force all write calls to be 1 byte. Limit the conversion
to the stdio layer, so that read() and write() work the same as
the FileHandle methods - this seems less confusing.
pull/5571/head
Kevin Bracey 2017-11-23 17:44:33 +02:00
parent 96c709fb35
commit f79bfddcad
3 changed files with 352 additions and 132 deletions

View File

@ -2,7 +2,17 @@
"name": "platform",
"config": {
"stdio-convert-newlines": {
"help": "Enable conversion to standard newlines on stdin/stdout",
"help": "Enable conversion to standard newlines on stdin/stdout/stderr",
"value": false
},
"stdio-convert-tty-newlines": {
"help": "Enable conversion to standard newlines on any tty FILE stream",
"value": false
},
"stdio-buffered-serial": {
"help": "Use UARTSerial driver to obtain buffered serial I/O on stdin/stdout/stderr. If false, unbuffered serial_getc and serial_putc are used directly.",
"value": false
},

View File

@ -28,11 +28,15 @@
#include "platform/mbed_critical.h"
#include "platform/mbed_poll.h"
#include "platform/PlatformMutex.h"
#include "drivers/UARTSerial.h"
#include "us_ticker_api.h"
#include "lp_ticker_api.h"
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#ifndef SSIZE_MAX
#define SSIZE_MAX INT_MAX
#endif
#include <stdio.h>
#include <errno.h>
#include "platform/mbed_retarget.h"
@ -66,7 +70,7 @@ static SingletonPtr<PlatformMutex> _mutex;
# define PREFIX(x) x
#endif
#define FILE_HANDLE_RESERVED 0xFFFFFFFF
#define FILE_HANDLE_RESERVED ((FileHandle*)0xFFFFFFFF)
using namespace mbed;
@ -89,7 +93,9 @@ uint32_t mbed_heap_size = 0;
* we can't just return a Filehandle* from _open and instead have to
* put it in a filehandles array and return the index into that array
*/
static FileHandle *filehandles[OPEN_MAX];
static FileHandle *filehandles[OPEN_MAX] = { FILE_HANDLE_RESERVED, FILE_HANDLE_RESERVED, FILE_HANDLE_RESERVED };
static char stdio_in_prev[OPEN_MAX];
static char stdio_out_prev[OPEN_MAX];
static SingletonPtr<PlatformMutex> filehandle_mutex;
namespace mbed {
@ -110,20 +116,138 @@ void remove_filehandle(FileHandle *file) {
#if DEVICE_SERIAL
extern int stdio_uart_inited;
extern serial_t stdio_uart;
#if MBED_CONF_PLATFORM_STDIO_CONVERT_NEWLINES
static char stdio_in_prev;
static char stdio_out_prev;
#endif
#endif
static void init_serial() {
#if DEVICE_SERIAL
/* Private FileHandle to implement backwards-compatible functionality of
* direct HAL serial access for default stdin/stdout/stderr.
* This is not a particularly well-behaved FileHandle for a stream, which
* is why it's not public. People should be using UARTSerial.
*/
class DirectSerial : public FileHandle {
public:
DirectSerial(PinName tx, PinName rx, int baud);
virtual ssize_t write(const void *buffer, size_t size);
virtual ssize_t read(void *buffer, size_t size);
virtual off_t seek(off_t offset, int whence = SEEK_SET) {
return -ESPIPE;
}
virtual off_t size() {
return -EINVAL;
}
virtual int isatty() {
return true;
}
virtual int close() {
return 0;
}
virtual short poll(short events) const;
};
DirectSerial::DirectSerial(PinName tx, PinName rx, int baud) {
if (stdio_uart_inited) return;
serial_init(&stdio_uart, STDIO_UART_TX, STDIO_UART_RX);
#if MBED_CONF_PLATFORM_STDIO_BAUD_RATE
serial_baud(&stdio_uart, MBED_CONF_PLATFORM_STDIO_BAUD_RATE);
#endif
serial_init(&stdio_uart, tx, rx);
serial_baud(&stdio_uart, baud);
}
ssize_t DirectSerial::write(const void *buffer, size_t size) {
const unsigned char *buf = static_cast<const unsigned char *>(buffer);
for (size_t i = 0; i < size; i++) {
serial_putc(&stdio_uart, buf[i]);
}
return size;
}
ssize_t DirectSerial::read(void *buffer, size_t size) {
unsigned char *buf = static_cast<unsigned char *>(buffer);
if (size == 0) {
return 0;
}
buf[0] = serial_getc(&stdio_uart);
return 1;
}
short DirectSerial::poll(short events) const {
short revents = 0;
if ((events & POLLIN) && serial_readable(&stdio_uart)) {
revents |= POLLIN;
}
if ((events & POLLOUT) && serial_writable(&stdio_uart)) {
revents |= POLLOUT;
}
return revents;
}
class Sink : public FileHandle {
public:
virtual ssize_t write(const void *buffer, size_t size);
virtual ssize_t read(void *buffer, size_t size);
virtual off_t seek(off_t offset, int whence = SEEK_SET) { return ESPIPE; }
virtual off_t size() { return -EINVAL; }
virtual int isatty() { return true; }
virtual int close() { return 0; }
};
ssize_t Sink::write(const void *buffer, size_t size) {
// Just swallow the data - this is historical non-DEVICE_SERIAL behaviour
return size;
}
ssize_t Sink::read(void *buffer, size_t size) {
// Produce 1 zero byte - historical behaviour returned 1 without touching
// the buffer
unsigned char *buf = static_cast<unsigned char *>(buffer);
buf[0] = 0;
return 1;
}
MBED_WEAK FileHandle* mbed::mbed_target_override_console(int fd)
{
return NULL;
}
MBED_WEAK FileHandle* mbed::mbed_override_console(int fd)
{
return NULL;
}
static FileHandle* default_console()
{
#if DEVICE_SERIAL
# if MBED_CONF_PLATFORM_STDIO_BUFFERED_SERIAL
static UARTSerial console(STDIO_UART_TX, STDIO_UART_RX, MBED_CONF_PLATFORM_STDIO_BAUD_RATE);
# else
static DirectSerial console(STDIO_UART_TX, STDIO_UART_RX, MBED_CONF_PLATFORM_STDIO_BAUD_RATE);
# endif
#else // DEVICE_SERIAL
static Sink console;
#endif
return &console;
}
/* Locate the default console for stdout, stdin, stderr */
static FileHandle* get_console(int fd) {
FileHandle *fh = mbed_override_console(fd);
if (fh) {
return fh;
}
fh = mbed_target_override_console(fd);
if (fh) {
return fh;
}
return default_console();
}
/* Deal with the fact C library may not _open descriptors 0, 1, 2 - auto bind */
static FileHandle* get_fhc(int fd) {
if (fd >= OPEN_MAX) {
return NULL;
}
FileHandle *fh = filehandles[fd];
if (fh == FILE_HANDLE_RESERVED && fd < 3) {
filehandles[fd] = fh = get_console(fd);
}
return fh;
}
/**
@ -189,7 +313,7 @@ static int reserve_filehandle() {
filehandle_mutex->unlock();
return -1;
}
filehandles[fh_i] = (FileHandle*)FILE_HANDLE_RESERVED;
filehandles[fh_i] = FILE_HANDLE_RESERVED;
filehandle_mutex->unlock();
return fh_i;
@ -202,6 +326,8 @@ int mbed::bind_to_fd(FileHandle *fh) {
}
filehandles[fh_i] = fh;
stdio_in_prev[fh_i] = 0;
stdio_out_prev[fh_i] = 0;
return fh_i;
}
@ -285,19 +411,21 @@ extern "C" FILEHANDLE PREFIX(_open)(const char *name, int openflags) {
// Before version 5.03, we were using a patched version of microlib with proper names
// This is the workaround that the microlib author suggested us
static int n = 0;
if (!std::strcmp(name, ":tt")) return n++;
if (std::strcmp(name, ":tt") == 0 && n < 3) {
return n++;
}
#else
/* Use the posix convention that stdin,out,err are filehandles 0,1,2.
*/
if (std::strcmp(name, __stdin_name) == 0) {
init_serial();
return 0;
get_fhc(STDIN_FILENO);
return STDIN_FILENO;
} else if (std::strcmp(name, __stdout_name) == 0) {
init_serial();
return 1;
get_fhc(STDOUT_FILENO);
return STDOUT_FILENO;
} else if (std::strcmp(name, __stderr_name) == 0) {
init_serial();
return 2;
get_fhc(STDERR_FILENO);
return STDERR_FILENO;
}
#endif
#ifndef __IAR_SYSTEMS_ICC__
@ -341,6 +469,8 @@ extern "C" int open(const char *name, int oflag, ...) {
}
filehandles[fh_i] = res;
stdio_in_prev[fh_i] = 0;
stdio_out_prev[fh_i] = 0;
return fh_i;
}
@ -350,7 +480,7 @@ extern "C" int PREFIX(_close)(FILEHANDLE fh) {
}
extern "C" int close(int fh) {
FileHandle* fhc = filehandles[fh];
FileHandle* fhc = get_fhc(fh);
filehandles[fh] = NULL;
if (fhc == NULL) {
errno = EBADF;
@ -366,15 +496,88 @@ extern "C" int close(int fh) {
}
}
static bool convert_crlf(int fd) {
#if MBED_CONF_PLATFORM_STDIO_CONVERT_TTY_NEWLINES
return isatty(fd);
#elif MBED_CONF_PLATFORM_STDIO_CONVERT_NEWLINES
return fd < 3 && isatty(fd);
#else
return false;
#endif
}
#if defined(__ICCARM__)
extern "C" size_t __write (int fh, const unsigned char *buffer, size_t length) {
#else
extern "C" int PREFIX(_write)(FILEHANDLE fh, const unsigned char *buffer, unsigned int length, int mode) {
#endif
ssize_t written = write(fh, buffer, length);
#if defined(MBED_TRAP_ERRORS_ENABLED) && MBED_TRAP_ERRORS_ENABLED && defined(MBED_CONF_RTOS_PRESENT)
if (core_util_is_isr_active() || !core_util_are_interrupts_enabled()) {
error("Error - writing to a file in an ISR or critical section\r\n");
}
#endif
if (length > SSIZE_MAX) {
errno = EINVAL;
return -1;
}
ssize_t slength = length;
ssize_t written = 0;
if (convert_crlf(fh)) {
// local prev is previous in buffer during seek
// stdio_out_prev[fh] is last thing actually written
char prev = stdio_out_prev[fh];
// Seek for '\n' without preceding '\r'; if found flush
// preceding and insert '\r'. Continue until end of input.
for (ssize_t cur = 0; cur < slength; cur++) {
if (buffer[cur] == '\n' && prev != '\r') {
ssize_t r;
// flush stuff preceding the \n
if (cur > written) {
r = write(fh, buffer + written, cur - written);
if (r < 0) {
return -1;
}
written += r;
if (written < cur) {
// For some reason, didn't write all - give up now
goto finish;
}
stdio_out_prev[fh] = prev;
}
// insert a \r now, leaving the \n still to be written
r = write(fh, "\r", 1);
if (r < 0) {
return -1;
}
if (r < 1) {
goto finish;
}
stdio_out_prev[fh] = '\r';
}
prev = buffer[cur];
}
}
// Flush remaining from conversion, or the whole thing if no conversion
if (written < slength) {
ssize_t r = write(fh, buffer + written, slength - written);
if (r < 0) {
return -1;
}
written += r;
if (written > 0) {
stdio_out_prev[fh] = buffer[written - 1];
}
}
finish:
#ifdef __ARMCC_VERSION
if (written >= 0) {
return (ssize_t)length - written;
return slength - written;
} else {
return written;
}
@ -384,46 +587,20 @@ extern "C" int PREFIX(_write)(FILEHANDLE fh, const unsigned char *buffer, unsign
}
extern "C" ssize_t write(int fh, const void *buf, size_t length) {
const unsigned char *buffer = static_cast<const unsigned char *>(buf);
int n; // n is the number of bytes written
#if defined(MBED_TRAP_ERRORS_ENABLED) && MBED_TRAP_ERRORS_ENABLED && defined(MBED_CONF_RTOS_PRESENT)
if (core_util_is_isr_active() || !core_util_are_interrupts_enabled()) {
error("Error - writing to a file in an ISR or critical section\r\n");
FileHandle* fhc = get_fhc(fh);
if (fhc == NULL) {
errno = EBADF;
return -1;
}
#endif
FileHandle* fhc = filehandles[fh];
if (fhc == NULL && fh < 3) {
#if DEVICE_SERIAL
if (!stdio_uart_inited) init_serial();
#if MBED_CONF_PLATFORM_STDIO_CONVERT_NEWLINES
for (unsigned int i = 0; i < length; i++) {
if (buffer[i] == '\n' && stdio_out_prev != '\r') {
serial_putc(&stdio_uart, '\r');
}
serial_putc(&stdio_uart, buffer[i]);
stdio_out_prev = buffer[i];
}
#else
for (unsigned int i = 0; i < length; i++) {
serial_putc(&stdio_uart, buffer[i]);
}
#endif
#endif
n = length;
ssize_t ret = fhc->write(buf, length);
if (ret < 0) {
errno = -ret;
return -1;
} else {
if (fhc == NULL) {
errno = EBADF;
return -1;
}
n = fhc->write(buffer, length);
if (n < 0) {
errno = -n;
}
return ret;
}
return n;
}
#if defined (__ARMCC_VERSION) && (__ARMCC_VERSION >= 6010050)
@ -432,9 +609,8 @@ extern "C" void PREFIX(_exit)(int return_code) {
}
extern "C" void _ttywrch(int ch) {
#if DEVICE_SERIAL
serial_putc(&stdio_uart, ch);
#endif
char c = ch;
write(STDOUT_FILENO, &c, 1);
}
#endif
@ -443,7 +619,50 @@ extern "C" size_t __read (int fh, unsigned char *buffer, size_t
#else
extern "C" int PREFIX(_read)(FILEHANDLE fh, unsigned char *buffer, unsigned int length, int mode) {
#endif
ssize_t bytes_read = read(fh, buffer, length);
#if defined(MBED_TRAP_ERRORS_ENABLED) && MBED_TRAP_ERRORS_ENABLED && defined(MBED_CONF_RTOS_PRESENT)
if (core_util_is_isr_active() || !core_util_are_interrupts_enabled()) {
error("Error - reading from a file in an ISR or critical section\r\n");
}
#endif
if (length > SSIZE_MAX) {
errno = EINVAL;
return -1;
}
ssize_t bytes_read = 0;
if (convert_crlf(fh)) {
while (true) {
char c;
ssize_t r = read(fh, &c, 1);
if (r < 0) {
return -1;
}
if (r == 0) {
return bytes_read;
}
if ((c == '\r' && stdio_in_prev[fh] != '\n') ||
(c == '\n' && stdio_in_prev[fh] != '\r')) {
stdio_in_prev[fh] = c;
*buffer = '\n';
break;
} else if ((c == '\r' && stdio_in_prev[fh] == '\n') ||
(c == '\n' && stdio_in_prev[fh] == '\r')) {
stdio_in_prev[fh] = c;
continue;
} else {
stdio_in_prev[fh] = c;
*buffer = c;
break;
}
}
bytes_read = 1;
} else {
bytes_read = read(fh, buffer, length);
}
#ifdef __ARMCC_VERSION
if (bytes_read < 0) {
return -1;
@ -458,58 +677,23 @@ extern "C" int PREFIX(_read)(FILEHANDLE fh, unsigned char *buffer, unsigned int
}
extern "C" ssize_t read(int fh, void *buf, size_t length) {
unsigned char *buffer = static_cast<unsigned char *>(buf);
int n; // n is the number of bytes read
#if defined(MBED_TRAP_ERRORS_ENABLED) && MBED_TRAP_ERRORS_ENABLED && defined(MBED_CONF_RTOS_PRESENT)
if (core_util_is_isr_active() || !core_util_are_interrupts_enabled()) {
error("Error - reading from a file in an ISR or critical section\r\n");
FileHandle* fhc = get_fhc(fh);
if (fhc == NULL) {
errno = EBADF;
return -1;
}
#endif
FileHandle* fhc = filehandles[fh];
if (fhc == NULL && fh < 3) {
// only read a character at a time from stdin
#if DEVICE_SERIAL
if (!stdio_uart_inited) init_serial();
#if MBED_CONF_PLATFORM_STDIO_CONVERT_NEWLINES
while (true) {
char c = serial_getc(&stdio_uart);
if ((c == '\r' && stdio_in_prev != '\n') ||
(c == '\n' && stdio_in_prev != '\r')) {
stdio_in_prev = c;
*buffer = '\n';
break;
} else if ((c == '\r' && stdio_in_prev == '\n') ||
(c == '\n' && stdio_in_prev == '\r')) {
stdio_in_prev = c;
// onto next character
continue;
} else {
stdio_in_prev = c;
*buffer = c;
break;
}
}
#else
*buffer = serial_getc(&stdio_uart);
#endif
#endif
n = 1;
ssize_t ret = fhc->read(buf, length);
if (ret < 0) {
errno = -ret;
return -1;
} else {
if (fhc == NULL) {
errno = EBADF;
return -1;
}
n = fhc->read(buffer, length);
if (n < 0) {
errno = -n;
}
return ret;
}
return n;
}
#ifdef __ARMCC_VERSION
extern "C" int PREFIX(_istty)(FILEHANDLE fh)
#else
@ -520,11 +704,8 @@ extern "C" int _isatty(FILEHANDLE fh)
}
extern "C" int isatty(int fh) {
FileHandle* fhc = filehandles[fh];
FileHandle* fhc = get_fhc(fh);
if (fhc == NULL) {
/* stdin, stdout and stderr should be tty */
if (fh < 3) return 1;
errno = EBADF;
return 0;
}
@ -561,12 +742,7 @@ int _lseek(FILEHANDLE fh, int offset, int whence)
}
extern "C" off_t lseek(int fh, off_t offset, int whence) {
FileHandle* fhc = filehandles[fh];
if (fhc == NULL && fh < 3) {
errno = ESPIPE;
return -1;
}
FileHandle* fhc = get_fhc(fh);
if (fhc == NULL) {
errno = EBADF;
return -1;
@ -587,7 +763,7 @@ extern "C" int PREFIX(_ensure)(FILEHANDLE fh) {
#endif
extern "C" int fsync(int fh) {
FileHandle* fhc = filehandles[fh];
FileHandle* fhc = get_fhc(fh);
if (fhc == NULL) {
errno = EBADF;
return -1;
@ -604,12 +780,7 @@ extern "C" int fsync(int fh) {
#ifdef __ARMCC_VERSION
extern "C" long PREFIX(_flen)(FILEHANDLE fh) {
FileHandle* fhc = filehandles[fh];
if (fhc == NULL && fh < 3) {
errno = EINVAL;
return -1;
}
FileHandle* fhc = get_fhc(fh);
if (fhc == NULL) {
errno = EBADF;
return -1;
@ -656,12 +827,7 @@ extern "C" int _fstat(int fh, struct stat *st) {
#endif
extern "C" int fstat(int fh, struct stat *st) {
FileHandle* fhc = filehandles[fh];
if (fhc == NULL && fh < 3) {
st->st_mode = S_IFCHR;
return 0;
}
FileHandle* fhc = get_fhc(fh);
if (fhc == NULL) {
errno = EBADF;
return -1;
@ -683,7 +849,7 @@ extern "C" int poll(struct pollfd fds[], nfds_t nfds, int timeout)
for (nfds_t n = 0; n < nfds; n++) {
// Underlying FileHandle poll returns POLLNVAL if given NULL, so
// we don't need to take special action.
fhs[n].fh = filehandles[fds[n].fd];
fhs[n].fh = get_fhc(fds[n].fd);
fhs[n].events = fds[n].events;
}
int ret = poll(fhs, nfds, timeout);

View File

@ -54,6 +54,10 @@ typedef unsigned int gid_t; ///< Group ID
#define NAME_MAX 255 ///< Maximum size of a name in a file path
#define STDIN_FILENO 0
#define STDOUT_FILENO 1
#define STDERR_FILENO 2
#include <time.h>
/** \addtogroup platform */
@ -70,6 +74,46 @@ namespace mbed {
class FileHandle;
class DirHandle;
/** Targets may implement this to change stdin, stdout, stderr.
*
* If the application hasn't provided mbed_override_console, this is called
* to give the target a chance to specify a FileHandle for the console.
*
* If this is not provided or returns NULL, the console will be:
* - UARTSerial if configuration option "platform.stdio-buffered-serial" is
* true and the target has DEVICE_SERIAL;
* - Raw HAL serial via serial_getc and serial_putc if
* "platform.stdio-buffered-serial" is false and the target has DEVICE_SERIAL;
* - stdout/stderr will be a sink and stdin will input a stream of 0s if the
* target does not have DEVICE_SERIAL.
*
* @param fd file descriptor - STDIN_FILENO, STDOUT_FILENO or STDERR_FILENO
* @return pointer to FileHandle to override normal stream otherwise NULL
*/
FileHandle* mbed_target_override_console(int fd);
/** Applications may implement this to change stdin, stdout, stderr.
*
* This hook gives the application a chance to specify a custom FileHandle
* for the console.
*
* If this is not provided or returns NULL, the console will be specified
* by mbed_target_override_console, else will default to serial - see
* mbed_target_override_console for more details.
*
* Example:
* @code
* FileHandle* mbed::mbed_override_console(int) {
* static UARTSerial my_serial(D0, D1);
* return &my_serial;
* }
* @endcode
* @param fd file descriptor - STDIN_FILENO, STDOUT_FILENO or STDERR_FILENO
* @return pointer to FileHandle to override normal stream otherwise NULL
*/
FileHandle* mbed_override_console(int fd);
}
typedef mbed::DirHandle DIR;