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authorErik Andersen <andersen@codepoet.org>2000-05-14 04:16:35 +0000
committerErik Andersen <andersen@codepoet.org>2000-05-14 04:16:35 +0000
commit64bc6412188b141c010ac3b8e813b837dd991e80 (patch)
treeffa12b79ea4b13191754f54b872eb1a4f9e3a04b /libc/stdio/stdio.c
Initial revision
Diffstat (limited to 'libc/stdio/stdio.c')
-rw-r--r--libc/stdio/stdio.c925
1 files changed, 925 insertions, 0 deletions
diff --git a/libc/stdio/stdio.c b/libc/stdio/stdio.c
new file mode 100644
index 000000000..98d0ba3b4
--- /dev/null
+++ b/libc/stdio/stdio.c
@@ -0,0 +1,925 @@
+/* Copyright (C) 1996 Robert de Bath <rdebath@cix.compulink.co.uk>
+ * This file is part of the Linux-8086 C library and is distributed
+ * under the GNU Library General Public License.
+ */
+
+/* This is an implementation of the C standard IO package.
+ */
+
+#include <stdio.h>
+
+#include <fcntl.h>
+#include <sys/types.h>
+#include <malloc.h>
+#include <errno.h>
+
+#undef STUB_FWRITE
+
+extern FILE *__IO_list; /* For fflush at exit */
+
+#define FIXED_BUFFERS 2
+struct fixed_buffer {
+ unsigned char data[BUFSIZ];
+ int used;
+};
+
+extern struct fixed_buffer _fixed_buffers[2];
+
+#define Inline_init __io_init_vars()
+
+#ifdef L__stdio_init
+
+#define buferr (stderr->unbuf) /* Stderr is unbuffered */
+
+FILE *__IO_list = 0; /* For fflush at exit */
+
+#if 0
+static char bufin[BUFSIZ];
+static char bufout[BUFSIZ];
+#ifndef buferr
+static char buferr[BUFSIZ];
+#endif
+
+#else
+static char *bufin;
+static char *bufout;
+#ifndef buferr
+static char *buferr;
+#endif
+#endif
+
+FILE stdin[1] =
+{
+#if 0
+ {bufin, bufin, bufin, bufin, bufin + sizeof(bufin),
+#else
+ {0, 0, 0, 0, 0,
+#endif
+ 0, _IOFBF | __MODE_READ | __MODE_IOTRAN}
+};
+
+FILE stdout[1] =
+{
+#if 0
+ {bufout, bufout, bufout, bufout, bufout + sizeof(bufout),
+#else
+ {0, 0, 0, 0, 0,
+#endif
+ 1, _IOFBF | __MODE_WRITE | __MODE_IOTRAN}
+};
+
+FILE stderr[1] =
+{
+#if 0
+ {buferr, buferr, buferr, buferr, buferr + sizeof(buferr),
+#else
+ {0, 0, 0, 0, 0,
+#endif
+ 2, _IONBF | __MODE_WRITE | __MODE_IOTRAN}
+};
+
+/* Call the stdio initiliser; it's main job it to call atexit */
+
+#define STATIC
+
+STATIC int
+__stdio_close_all()
+{
+ FILE *fp;
+ fflush(stdout);
+ fflush(stderr);
+ for (fp = __IO_list; fp; fp = fp->next)
+ {
+ fflush(fp);
+ close(fp->fd);
+ /* Note we're not de-allocating the memory */
+ /* There doesn't seem to be much point :-) */
+ fp->fd = -1;
+ }
+}
+
+static int first_time = 0;
+
+struct fixed_buffer _fixed_buffers[2];
+
+
+STATIC void
+__io_init_vars()
+{
+ if( first_time ) return;
+ first_time = 1;
+
+ stdin->bufpos = bufin = _fixed_buffers[0].data; /*(char *)malloc(BUFSIZ)*/;
+ stdin->bufread = bufin;
+ stdin->bufwrite = bufin;
+ stdin->bufstart = bufin;
+ stdin->bufend = bufin + sizeof(bufin);
+ stdin->fd = 0;
+ stdin->mode = _IOFBF | __MODE_READ | __MODE_IOTRAN | __MODE_FREEBUF;
+
+ _fixed_buffers[0].used = 1;
+
+ stdout->bufpos = bufout = _fixed_buffers[1].data; /*(char *)malloc(BUFSIZ);*/
+ stdout->bufread = bufout;
+ stdout->bufwrite = bufout;
+ stdout->bufstart = bufout;
+ stdout->bufend = bufout + sizeof(bufout);
+ stdout->fd = 1;
+ stdout->mode = _IOFBF | __MODE_WRITE | __MODE_IOTRAN | __MODE_FREEBUF;
+
+ _fixed_buffers[1].used = 1;
+
+#if 0
+ stderr->bufpos = buferr = (char *)malloc(BUFSIZ);
+#else
+ stderr->bufpos = buferr;
+#endif
+ stderr->bufread = buferr;
+ stderr->bufwrite = buferr;
+ stderr->bufstart = buferr;
+ stderr->bufend = buferr + sizeof(buferr);
+ stderr->fd = 2;
+ stderr->mode = _IONBF | __MODE_WRITE | __MODE_IOTRAN;
+
+ if (isatty(1))
+ stdout->mode |= _IOLBF;
+ atexit(__stdio_close_all);
+}
+#endif
+
+#ifdef L_fputc
+int
+fputc(ch, fp)
+int ch;
+FILE *fp;
+{
+ register int v;
+ Inline_init;
+
+ v = fp->mode;
+ /* If last op was a read ... */
+ if ((v & __MODE_READING) && fflush(fp))
+ return EOF;
+
+ /* Can't write or there's been an EOF or error then return EOF */
+ if ((v & (__MODE_WRITE | __MODE_EOF | __MODE_ERR)) != __MODE_WRITE)
+ return EOF;
+
+ /* In MSDOS translation mode */
+#if __MODE_IOTRAN
+ if (ch == '\n' && (v & __MODE_IOTRAN) && fputc('\r', fp) == EOF)
+ return EOF;
+#endif
+
+ /* Buffer is full */
+ if (fp->bufpos >= fp->bufend && fflush(fp))
+ return EOF;
+
+ /* Right! Do it! */
+ *(fp->bufpos++) = ch;
+ fp->mode |= __MODE_WRITING;
+
+ /* Unbuffered or Line buffered and end of line */
+ if (((ch == '\n' && (v & _IOLBF)) || (v & _IONBF))
+ && fflush(fp))
+ return EOF;
+
+ /* Can the macro handle this by itself ? */
+ if (v & (__MODE_IOTRAN | _IOLBF | _IONBF))
+ fp->bufwrite = fp->bufstart; /* Nope */
+ else
+ fp->bufwrite = fp->bufend; /* Yup */
+
+ /* Correct return val */
+ return (unsigned char) ch;
+}
+#endif
+
+#ifdef L_fgetc
+int
+fgetc(fp)
+FILE *fp;
+{
+ int ch;
+ Inline_init;
+
+ if (fp->mode & __MODE_WRITING)
+ fflush(fp);
+
+ try_again:
+ /* Can't read or there's been an EOF or error then return EOF */
+ if ((fp->mode & (__MODE_READ | __MODE_EOF | __MODE_ERR)) != __MODE_READ)
+ return EOF;
+
+ /* Nothing in the buffer - fill it up */
+ if (fp->bufpos >= fp->bufread)
+ {
+ fp->bufpos = fp->bufread = fp->bufstart;
+ ch = fread(fp->bufpos, 1, fp->bufend - fp->bufstart, fp);
+ if (ch == 0)
+ return EOF;
+ fp->bufread += ch;
+ fp->mode |= __MODE_READING;
+ fp->mode &= ~__MODE_UNGOT;
+ }
+ ch = *(fp->bufpos++);
+
+#if __MODE_IOTRAN
+ /* In MSDOS translation mode; WARN: Doesn't work with UNIX macro */
+ if (ch == '\r' && (fp->mode & __MODE_IOTRAN))
+ goto try_again;
+#endif
+
+ return ch;
+}
+#endif
+
+#ifdef L_fflush
+int
+fflush(fp)
+FILE *fp;
+{
+ int len, cc, rv=0;
+ char * bstart;
+ if (fp == NULL) /* On NULL flush the lot. */
+ {
+ if (fflush(stdin))
+ return EOF;
+ if (fflush(stdout))
+ return EOF;
+ if (fflush(stderr))
+ return EOF;
+
+ for (fp = __IO_list; fp; fp = fp->next)
+ if (fflush(fp))
+ return EOF;
+
+ return 0;
+ }
+
+ /* If there's output data pending */
+ if (fp->mode & __MODE_WRITING)
+ {
+ len = fp->bufpos - fp->bufstart;
+
+ if (len)
+ {
+ bstart = fp->bufstart;
+ /*
+ * The loop is so we don't get upset by signals or partial writes.
+ */
+ do
+ {
+ cc = write(fp->fd, bstart, len);
+ if( cc > 0 )
+ {
+ bstart+=cc; len-=cc;
+ }
+ }
+ while ( cc>0 || (cc == -1 && errno == EINTR));
+ /*
+ * If we get here with len!=0 there was an error, exactly what to
+ * do about it is another matter ...
+ *
+ * I'll just clear the buffer.
+ */
+ if (len)
+ {
+ fp->mode |= __MODE_ERR;
+ rv = EOF;
+ }
+ }
+ }
+ /* If there's data in the buffer sychronise the file positions */
+ else if (fp->mode & __MODE_READING)
+ {
+ /* Humm, I think this means sync the file like fpurge() ... */
+ /* Anyway the user isn't supposed to call this function when reading */
+
+ len = fp->bufread - fp->bufpos; /* Bytes buffered but unread */
+ /* If it's a file, make it good */
+ if (len > 0 && lseek(fp->fd, (long)-len, 1) < 0)
+ {
+ /* Hummm - Not certain here, I don't think this is reported */
+ /*
+ * fp->mode |= __MODE_ERR; return EOF;
+ */
+ }
+ }
+
+ /* All done, no problem */
+ fp->mode &= (~(__MODE_READING|__MODE_WRITING|__MODE_EOF|__MODE_UNGOT));
+ fp->bufread = fp->bufwrite = fp->bufpos = fp->bufstart;
+ return rv;
+}
+#endif
+
+#ifdef L_fgets
+/* Nothing special here ... */
+char *
+fgets(s, count, f)
+char *s;
+size_t count;
+FILE *f;
+{
+ char *ret;
+ register size_t i;
+ register int ch;
+
+ ret = s;
+ for (i = count; i > 0; i--)
+ {
+ ch = getc(f);
+ if (ch == EOF)
+ {
+ if (s == ret)
+ return 0;
+ break;
+ }
+ *s++ = (char) ch;
+ if (ch == '\n')
+ break;
+ }
+ *s = 0;
+
+ if (ferror(f))
+ return 0;
+ return ret;
+}
+#endif
+
+#ifdef L_gets
+char *
+gets(str) /* BAD function; DON'T use it! */
+char *str;
+{
+ /* Auwlright it will work but of course _your_ program will crash */
+ /* if it's given a too long line */
+ register char *p = str;
+ register int c;
+
+ while (((c = getc(stdin)) != EOF) && (c != '\n'))
+ *p++ = c;
+ *p = '\0';
+ return (((c == EOF) && (p == str)) ? NULL : str); /* NULL == EOF */
+}
+#endif
+
+#ifdef L_fputs
+int
+fputs(str, fp)
+char *str;
+FILE *fp;
+{
+ register int n = 0;
+ while (*str)
+ {
+ if (putc(*str++, fp) == EOF)
+ return (EOF);
+ ++n;
+ }
+ return (n);
+}
+#endif
+
+#ifdef L_puts
+int
+puts(str)
+char *str;
+{
+ register int n;
+
+ if (((n = fputs(str, stdout)) == EOF)
+ || (putc('\n', stdout) == EOF))
+ return (EOF);
+ return (++n);
+}
+#endif
+
+#ifdef L_fread
+/*
+ * fread will often be used to read in large chunks of data calling read()
+ * directly can be a big win in this case. Beware also fgetc calls this
+ * function to fill the buffer.
+ *
+ * This ignores __MODE__IOTRAN; probably exactly what you want. (It _is_ what
+ * fgetc wants)
+ */
+int
+fread(buf, size, nelm, fp)
+char *buf;
+int size;
+int nelm;
+FILE *fp;
+{
+ int len, v;
+ unsigned bytes, got = 0;
+ Inline_init;
+
+ v = fp->mode;
+
+ /* Want to do this to bring the file pointer up to date */
+ if (v & __MODE_WRITING)
+ fflush(fp);
+
+ /* Can't read or there's been an EOF or error then return zero */
+ if ((v & (__MODE_READ | __MODE_EOF | __MODE_ERR)) != __MODE_READ)
+ return 0;
+
+ /* This could be long, doesn't seem much point tho */
+ bytes = size * nelm;
+
+ len = fp->bufread - fp->bufpos;
+ if (len >= bytes) /* Enough buffered */
+ {
+ memcpy(buf, fp->bufpos, (unsigned) bytes);
+ fp->bufpos += bytes;
+ return bytes;
+ }
+ else if (len > 0) /* Some buffered */
+ {
+ memcpy(buf, fp->bufpos, len);
+ got = len;
+ }
+
+ /* Need more; do it with a direct read */
+ len = read(fp->fd, buf + got, (unsigned) (bytes - got));
+
+ /* Possibly for now _or_ later */
+ if (len < 0)
+ {
+ fp->mode |= __MODE_ERR;
+ len = 0;
+ }
+ else if (len == 0)
+ fp->mode |= __MODE_EOF;
+
+ return (got + len) / size;
+}
+#endif
+
+#ifdef L_fwrite
+/*
+ * Like fread, fwrite will often be used to write out large chunks of
+ * data; calling write() directly can be a big win in this case.
+ *
+ * But first we check to see if there's space in the buffer.
+ *
+ * Again this ignores __MODE__IOTRAN.
+ */
+int
+fwrite(buf, size, nelm, fp)
+char *buf;
+int size;
+int nelm;
+FILE *fp;
+{
+ register int v;
+ int len;
+ unsigned bytes, put;
+
+#ifdef STUB_FWRITE
+ bytes = size * nelm;
+ while(bytes>0) {
+ len=write(fp->fd, buf, bytes);
+ if (len<=0) {
+ break;
+ }
+ bytes -= len;
+ buf += len;
+ }
+ return nelm;
+#else
+
+ v = fp->mode;
+ /* If last op was a read ... */
+ if ((v & __MODE_READING) && fflush(fp))
+ return 0;
+
+ /* Can't write or there's been an EOF or error then return 0 */
+ if ((v & (__MODE_WRITE | __MODE_EOF | __MODE_ERR)) != __MODE_WRITE)
+ return 0;
+
+ /* This could be long, doesn't seem much point tho */
+ bytes = size * nelm;
+
+ len = fp->bufend - fp->bufpos;
+
+ /* Flush the buffer if not enough room */
+ if (bytes > len)
+ if (fflush(fp))
+ return 0;
+
+ len = fp->bufend - fp->bufpos;
+ if (bytes <= len) /* It'll fit in the buffer ? */
+ {
+ fp->mode |= __MODE_WRITING;
+ memcpy(fp->bufpos, buf, bytes);
+ fp->bufpos += bytes;
+
+ /* If we're not fully buffered */
+ if (v & (_IOLBF | _IONBF))
+ fflush(fp);
+
+ return nelm;
+ }
+ else
+ /* Too big for the buffer */
+ {
+ put = bytes;
+ do
+ {
+ len = write(fp->fd, buf, bytes);
+ if( len > 0 )
+ {
+ buf+=len; bytes-=len;
+ }
+ }
+ while (len > 0 || (len == -1 && errno == EINTR));
+
+ if (len < 0)
+ fp->mode |= __MODE_ERR;
+
+ put -= bytes;
+ }
+
+ return put / size;
+#endif
+}
+#endif
+
+#ifdef L_rewind
+void
+rewind(fp)
+FILE * fp;
+{
+ fseek(fp, (long)0, 0);
+ clearerr(fp);
+}
+#endif
+
+#ifdef L_fseek
+int
+fseek(fp, offset, ref)
+FILE *fp;
+long offset;
+int ref;
+{
+#if 0
+ /* FIXME: this is broken! BROKEN!!!! */
+ /* if __MODE_READING and no ungetc ever done can just move pointer */
+ /* This needs testing! */
+
+ if ( (fp->mode &(__MODE_READING | __MODE_UNGOT)) == __MODE_READING &&
+ ( ref == SEEK_SET || ref == SEEK_CUR ))
+ {
+ long fpos = lseek(fp->fd, 0L, SEEK_CUR);
+ if( fpos == -1 ) return EOF;
+
+ if( ref == SEEK_CUR )
+ {
+ ref = SEEK_SET;
+ offset = fpos + offset + fp->bufpos - fp->bufread;
+ }
+ if( ref == SEEK_SET )
+ {
+ if ( offset < fpos && offset >= fpos + fp->bufstart - fp->bufread )
+ {
+ fp->bufpos = offset - fpos + fp->bufread;
+ return 0;
+ }
+ }
+ }
+#endif
+
+ /* Use fflush to sync the pointers */
+
+ if (fflush(fp) == EOF)
+ return EOF;
+ if (lseek(fp->fd, offset, ref) < 0)
+ return EOF;
+ return 0;
+}
+#endif
+
+#ifdef L_ftell
+long ftell(fp)
+FILE * fp;
+{
+ long rv;
+ if (fflush(fp) == EOF)
+ return EOF;
+ return lseek(fp->fd, 0L, SEEK_CUR);
+}
+#endif
+
+#ifdef L_fopen
+/*
+ * This Fopen is all three of fopen, fdopen and freopen. The macros in
+ * stdio.h show the other names.
+ */
+FILE *
+__fopen(fname, fd, fp, mode)
+char *fname;
+int fd;
+FILE *fp;
+char *mode;
+{
+ int open_mode = 0;
+#if __MODE_IOTRAN
+ int do_iosense = 1;
+#endif
+ int fopen_mode = 0;
+ FILE *nfp = 0;
+
+ /* If we've got an fp close the old one (freopen) */
+ if (fp)
+ {
+ /* Careful, don't de-allocate it */
+ fopen_mode |= (fp->mode & (__MODE_BUF | __MODE_FREEFIL | __MODE_FREEBUF));
+ fp->mode &= ~(__MODE_FREEFIL | __MODE_FREEBUF);
+ fclose(fp);
+ }
+
+ /* decode the new open mode */
+ while (*mode)
+ switch (*mode++)
+ {
+ case 'r':
+ fopen_mode |= __MODE_READ;
+ break;
+ case 'w':
+ fopen_mode |= __MODE_WRITE;
+ open_mode = (O_CREAT | O_TRUNC);
+ break;
+ case 'a':
+ fopen_mode |= __MODE_WRITE;
+ open_mode = (O_CREAT | O_APPEND);
+ break;
+ case '+':
+ fopen_mode |= __MODE_RDWR;
+ break;
+#if __MODE_IOTRAN
+ case 'b': /* Binary */
+ fopen_mode &= ~__MODE_IOTRAN;
+ do_iosense=0;
+ break;
+ case 't': /* Text */
+ fopen_mode |= __MODE_IOTRAN;
+ do_iosense=0;
+ break;
+#endif
+ }
+
+ /* Add in the read/write options to mode for open() */
+ switch (fopen_mode & (__MODE_READ | __MODE_WRITE))
+ {
+ case 0:
+ return 0;
+ case __MODE_READ:
+ open_mode |= O_RDONLY;
+ break;
+ case __MODE_WRITE:
+ open_mode |= O_WRONLY;
+ break;
+ default:
+ open_mode |= O_RDWR;
+ break;
+ }
+
+ /* Allocate the (FILE) before we do anything irreversable */
+ if (fp == 0)
+ {
+ nfp = malloc(sizeof(FILE));
+ if (nfp == 0)
+ return 0;
+ }
+
+ /* Open the file itself */
+ if (fname)
+ fd = open(fname, open_mode, 0666);
+ if (fd < 0) /* Grrrr */
+ {
+ if (nfp)
+ free(nfp);
+ return 0;
+ }
+
+ /* If this isn't freopen create a (FILE) and buffer for it */
+ if (fp == 0)
+ {
+ int i;
+ fp = nfp;
+ fp->next = __IO_list;
+ __IO_list = fp;
+
+ fp->mode = __MODE_FREEFIL;
+ if( isatty(fd) )
+ {
+ fp->mode |= _IOLBF;
+#if __MODE_IOTRAN
+ if( do_iosense ) fopen_mode |= __MODE_IOTRAN;
+#endif
+ }
+ else
+ fp->mode |= _IOFBF;
+
+ for(i=0;i<FIXED_BUFFERS;i++)
+ if (!_fixed_buffers[i].used) {
+ fp->bufstart = _fixed_buffers[i].data;
+ _fixed_buffers[i].used = 1;
+ break;
+ }
+
+ if (i == FIXED_BUFFERS)
+ fp->bufstart = malloc(BUFSIZ);
+
+ if (fp->bufstart == 0) /* Oops, no mem */
+ { /* Humm, full buffering with a two(!) byte
+ * buffer. */
+ fp->bufstart = fp->unbuf;
+ fp->bufend = fp->unbuf + sizeof(fp->unbuf);
+ }
+ else
+ {
+ fp->bufend = fp->bufstart + BUFSIZ;
+ fp->mode |= __MODE_FREEBUF;
+ }
+ }
+ /* Ok, file's ready clear the buffer and save important bits */
+ fp->bufpos = fp->bufread = fp->bufwrite = fp->bufstart;
+ fp->mode |= fopen_mode;
+ fp->fd = fd;
+ return fp;
+}
+#endif
+
+#ifdef L_fclose
+int
+fclose(fp)
+FILE *fp;
+{
+ int rv = 0;
+
+ if (fp == 0)
+ {
+ errno = EINVAL;
+ return EOF;
+ }
+ if (fflush(fp))
+ return EOF;
+
+ if (close(fp->fd))
+ rv = EOF;
+ fp->fd = -1;
+
+ if (fp->mode & __MODE_FREEBUF)
+ {
+ int i;
+ for(i=0;i<FIXED_BUFFERS;i++)
+ if (fp->bufstart == _fixed_buffers[i].data) {
+ _fixed_buffers[i].used = 0;
+ break;
+ }
+ if(i==FIXED_BUFFERS)
+ free(fp->bufstart);
+ fp->mode &= ~__MODE_FREEBUF;
+ fp->bufstart = fp->bufend = 0;
+ }
+
+ if (fp->mode & __MODE_FREEFIL)
+ {
+ FILE *prev = 0, *ptr;
+ fp->mode = 0;
+
+ for (ptr = __IO_list; ptr && ptr != fp; ptr = ptr->next)
+ ;
+ if (ptr == fp)
+ {
+ if (prev == 0)
+ __IO_list = fp->next;
+ else
+ prev->next = fp->next;
+ }
+ free(fp);
+ }
+ else
+ fp->mode = 0;
+
+ return rv;
+}
+#endif
+
+#ifdef L_setbuffer
+void
+setbuffer(fp, buf, size)
+FILE * fp;
+char * buf;
+int size;
+{
+ fflush(fp);
+
+ if ((fp->bufstart == (unsigned char*)buf) && (fp->bufend == ((unsigned char*)buf + size)))
+ return;
+
+ if( fp->mode & __MODE_FREEBUF ) {
+ int i;
+ for(i=0;i<FIXED_BUFFERS;i++)
+ if (fp->bufstart == _fixed_buffers[i].data) {
+ _fixed_buffers[i].used = 0;
+ break;
+ }
+ if(i==FIXED_BUFFERS)
+ free(fp->bufstart);
+ }
+ fp->mode &= ~(__MODE_FREEBUF|__MODE_BUF);
+
+ if( buf == 0 )
+ {
+ fp->bufstart = fp->unbuf;
+ fp->bufend = fp->unbuf + sizeof(fp->unbuf);
+ fp->mode |= _IONBF;
+ }
+ else
+ {
+ fp->bufstart = buf;
+ fp->bufend = buf+size;
+ fp->mode |= _IOFBF;
+ }
+ fp->bufpos = fp->bufread = fp->bufwrite = fp->bufstart;
+}
+#endif
+
+#ifdef L_setvbuf
+int setvbuf(fp, buf, mode, size)
+FILE * fp;
+char * buf;
+int mode;
+size_t size;
+{
+ fflush(fp);
+ if( fp->mode & __MODE_FREEBUF ) {
+ int i;
+ for(i=0;i<FIXED_BUFFERS;i++)
+ if (fp->bufstart == _fixed_buffers[i].data) {
+ _fixed_buffers[i].used = 0;
+ break;
+ }
+ if(i==FIXED_BUFFERS)
+ free(fp->bufstart);
+ }
+ fp->mode &= ~(__MODE_FREEBUF|__MODE_BUF);
+ fp->bufstart = fp->unbuf;
+ fp->bufend = fp->unbuf + sizeof(fp->unbuf);
+ fp->mode |= _IONBF;
+
+ if( mode == _IOFBF || mode == _IOLBF )
+ {
+ if( size <= 0 ) size = BUFSIZ;
+ if( buf == 0 )
+ if (size == BUFSIZ) {
+ int i;
+ for(i=0;i<FIXED_BUFFERS;i++)
+ if (!_fixed_buffers[i].used) {
+ _fixed_buffers[i].used = 1;
+ buf = _fixed_buffers[i].data;
+ break;
+ }
+ if(i==FIXED_BUFFERS)
+ buf = malloc(size);
+ } else
+ buf = malloc(size);
+ if( buf == 0 ) return EOF;
+
+ fp->bufstart = buf;
+ fp->bufend = buf+size;
+ fp->mode |= mode;
+ }
+ fp->bufpos = fp->bufread = fp->bufwrite = fp->bufstart;
+}
+#endif
+
+#ifdef L_ungetc
+int
+ungetc(c, fp)
+int c;
+FILE *fp;
+{
+ if (fp->mode & __MODE_WRITING)
+ fflush(fp);
+
+ /* Can't read or there's been an error then return EOF */
+ if ((fp->mode & (__MODE_READ | __MODE_ERR)) != __MODE_READ)
+ return EOF;
+
+ /* Can't do fast fseeks */
+ fp->mode |= __MODE_UNGOT;
+
+ if( fp->bufpos > fp->bufstart )
+ return *--fp->bufpos = (unsigned char) c;
+ else if( fp->bufread == fp->bufstart )
+ return *fp->bufread++ = (unsigned char) c;
+ else
+ return EOF;
+}
+#endif