Telodendria/src/Stream.c
Jordan Bancino 5289c16e2b Convert all code to new Stream API.
Also made a number of improvmements to tt, making it compatible with more
shells.
2023-03-18 14:32:09 +00:00

629 lines
11 KiB
C

/*
* Copyright (C) 2022-2023 Jordan Bancino <@jordan:bancino.net>
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation files
* (the "Software"), to deal in the Software without restriction,
* including without limitation the rights to use, copy, modify, merge,
* publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <Stream.h>
#include <Io.h>
#include <Memory.h>
#include <Util.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <sys/stat.h>
#ifndef STREAM_RETRIES
#define STREAM_RETRIES 10
#endif
#ifndef STREAM_DELAY
#define STREAM_DELAY 2
#endif
#define STREAM_EOF (1 << 0)
#define STREAM_ERR (1 << 1)
#define STREAM_TTY (1 << 2)
struct Stream
{
Io *io;
char *rBuf;
size_t rLen;
size_t rOff;
char *wBuf;
size_t wLen;
char *ugBuf;
size_t ugSize;
size_t ugLen;
int flags;
int fd;
};
Stream *
StreamIo(Io * io)
{
Stream *stream;
if (!io)
{
return NULL;
}
stream = Malloc(sizeof(Stream));
if (!stream)
{
return NULL;
}
memset(stream, 0, sizeof(Stream));
stream->io = io;
stream->fd = -1;
return stream;
}
Stream *
StreamFd(int fd)
{
Io *io = IoFd(fd);
Stream *stream;
if (!io)
{
return NULL;
}
stream = StreamIo(io);
if (!stream)
{
return NULL;
}
stream->fd = fd;
if (isatty(stream->fd))
{
stream->flags |= STREAM_TTY;
}
return stream;
}
Stream *
StreamFile(FILE * fp)
{
Io *io = IoFile(fp);
Stream *stream;
if (!io)
{
return NULL;
}
stream = StreamIo(io);
if (!stream)
{
return NULL;
}
stream->fd = fileno(fp);
if (isatty(stream->fd))
{
stream->flags |= STREAM_TTY;
}
return stream;
}
Stream *
StreamOpen(const char *path, const char *mode)
{
FILE *fp = fopen(path, mode);
if (!fp)
{
return NULL;
}
return StreamFile(fp);
}
Stream *
StreamStdout(void)
{
static Stream *stdOut = NULL;
if (!stdOut)
{
stdOut = StreamFd(STDOUT_FILENO);
}
return stdOut;
}
Stream *
StreamStderr(void)
{
static Stream *stdErr = NULL;
if (!stdErr)
{
stdErr = StreamFd(STDERR_FILENO);
}
return stdErr;
}
Stream *
StreamStdin(void)
{
static Stream *stdIn = NULL;
if (!stdIn)
{
stdIn = StreamFd(STDIN_FILENO);
}
return stdIn;
}
int
StreamClose(Stream * stream)
{
int ret = 0;
if (!stream)
{
errno = EBADF;
return EOF;
}
if (stream->rBuf)
{
Free(stream->rBuf);
}
if (stream->wBuf)
{
ssize_t writeRes = IoWrite(stream->io, stream->wBuf, stream->wLen);
Free(stream->wBuf);
if (writeRes == -1)
{
ret = EOF;
}
}
if (stream->ugBuf)
{
Free(stream->ugBuf);
}
ret = IoClose(stream->io);
Free(stream);
return ret;
}
int
StreamVprintf(Stream * stream, const char *fmt, va_list ap)
{
/* This might look like very similar code to IoVprintf(), but I
* chose not to defer to IoVprintf() because that would require us
* to immediately flush the buffer, since the Io API is unbuffered.
* StreamPuts() uses StreamPutc() under the hood, which is
* buffered. It therefore allows us to finish filling the buffer
* and then only flush it when necessary, preventing superfluous
* writes. */
char *buf = NULL;
size_t bufSize = 0;
FILE *fp;
int ret;
if (!stream || !fmt)
{
return -1;
}
fp = open_memstream(&buf, &bufSize);
if (!fp)
{
return -1;
}
ret = vfprintf(fp, fmt, ap);
fclose(fp);
if (ret >= 0)
{
ret = StreamPuts(stream, buf);
}
free(buf); /* Allocated by stdlib, not Memory
* API */
return ret;
}
int
StreamPrintf(Stream * stream, const char *fmt,...)
{
int ret;
va_list ap;
va_start(ap, fmt);
ret = StreamVprintf(stream, fmt, ap);
va_end(ap);
return ret;
}
int
StreamGetc(Stream * stream)
{
int c;
if (!stream)
{
errno = EBADF;
return EOF;
}
/* Empty the ungetc stack first */
if (stream->ugLen)
{
c = stream->ugBuf[stream->ugLen - 1];
stream->ugLen--;
return c;
}
if (stream->flags & EOF)
{
return EOF;
}
if (!stream->rBuf)
{
/* No buffer allocated yet */
stream->rBuf = Malloc(IO_BUFFER);
if (!stream->rBuf)
{
stream->flags |= STREAM_ERR;
return EOF;
}
stream->rOff = 0;
stream->rLen = 0;
}
if (stream->rOff >= stream->rLen)
{
/* We read through the entire buffer; get a new one */
ssize_t readRes = IoRead(stream->io, stream->rBuf, IO_BUFFER);
if (readRes == 0)
{
stream->flags |= STREAM_EOF;
return EOF;
}
if (readRes == -1)
{
stream->flags |= STREAM_ERR;
return EOF;
}
stream->rOff = 0;
stream->rLen = readRes;
}
/* Read the character in the buffer and advance the offset */
c = stream->rBuf[stream->rOff];
stream->rOff++;
return c;
}
int
StreamUngetc(Stream * stream, int c)
{
if (!stream)
{
errno = EBADF;
return EOF;
}
if (!stream->ugBuf)
{
stream->ugSize = IO_BUFFER;
stream->ugBuf = Malloc(stream->ugSize);
if (!stream->ugBuf)
{
stream->flags |= STREAM_ERR;
return EOF;
}
}
if (stream->ugLen >= stream->ugSize)
{
char *new;
stream->ugSize += IO_BUFFER;
new = Realloc(stream->ugBuf, stream->ugSize);
if (!new)
{
stream->flags |= STREAM_ERR;
Free(stream->ugBuf);
stream->ugBuf = NULL;
return EOF;
}
Free(stream->ugBuf);
stream->ugBuf = new;
}
stream->ugBuf[stream->ugLen] = c;
stream->ugLen++;
return c;
}
int
StreamPutc(Stream * stream, int c)
{
if (!stream)
{
errno = EBADF;
return EOF;
}
if (!stream->wBuf)
{
stream->wBuf = Malloc(IO_BUFFER);
if (!stream->wBuf)
{
stream->flags |= STREAM_ERR;
return EOF;
}
}
if (stream->wLen == IO_BUFFER)
{
/* Buffer full; write it */
ssize_t writeRes = IoWrite(stream->io, stream->wBuf, stream->wLen);
if (writeRes == -1)
{
stream->flags |= STREAM_ERR;
return EOF;
}
stream->wLen = 0;
}
stream->wBuf[stream->wLen] = c;
stream->wLen++;
if (stream->flags & STREAM_TTY && c == '\n')
{
/* Newline encountered on a TTY; write now. This fixes some
* strange behavior on certain TTYs where a newline is written
* to the screen upon flush even when no newline exists in the
* stream. We just flush on newlines, but only if we're
* directly writing to a TTY. */
ssize_t writeRes = IoWrite(stream->io, stream->wBuf, stream->wLen);
if (writeRes == -1)
{
stream->flags |= STREAM_ERR;
return EOF;
}
stream->wLen = 0;
}
return c;
}
int
StreamPuts(Stream * stream, char *str)
{
int ret = 0;
if (!stream)
{
errno = EBADF;
return -1;
}
while (*str)
{
if (StreamPutc(stream, *str) == EOF)
{
ret = -1;
break;
}
str++;
}
return ret;
}
char *
StreamGets(Stream * stream, char *str, int size)
{
int i;
if (!stream)
{
errno = EBADF;
return NULL;
}
if (size <= 0)
{
errno = EINVAL;
return NULL;
}
for (i = 0; i < size - 1; i++)
{
int c = StreamGetc(stream);
if (StreamEof(stream) || StreamError(stream))
{
break;
}
str[i] = c;
if (c == '\n')
{
i++;
break;
}
}
str[i] = '\0';
return str;
}
int
StreamEof(Stream * stream)
{
return stream && (stream->flags & STREAM_EOF);
}
int
StreamError(Stream * stream)
{
return stream && (stream->flags & STREAM_ERR);
}
void
StreamClearError(Stream * stream)
{
if (stream)
{
stream->flags &= ~STREAM_ERR;
}
}
int
StreamFlush(Stream * stream)
{
if (!stream)
{
errno = EBADF;
return EOF;
}
if (stream->wLen)
{
ssize_t writeRes = IoWrite(stream->io, stream->wBuf, stream->wLen);
if (writeRes == -1)
{
stream->flags |= STREAM_ERR;
return EOF;
}
stream->wLen = 0;
}
return 0;
}
ssize_t
StreamCopy(Stream * in, Stream * out)
{
ssize_t nBytes = 0;
int c;
int tries = 0;
int readFlg = 0;
while (1)
{
c = StreamGetc(in);
if (StreamEof(in))
{
break;
}
if (StreamError(in))
{
if (errno == EAGAIN)
{
StreamClearError(in);
tries++;
if (tries >= STREAM_RETRIES || readFlg)
{
break;
}
else
{
UtilSleepMillis(STREAM_DELAY);
continue;
}
}
else
{
break;
}
}
/* As soon as we've successfully read a byte, treat future
* EAGAINs as EOF, because somebody might have forgotten to
* close their stream. */
readFlg = 1;
tries = 0;
StreamPutc(out, c);
nBytes++;
}
StreamFlush(out);
return nBytes;
}
int
StreamFileno(Stream * stream)
{
return stream ? stream->fd : -1;
}