From dfc517b05395d925a4d7b1ce9633a849f9468e70 Mon Sep 17 00:00:00 2001 From: Jelmer Vernooij Date: Thu, 23 Feb 2006 15:52:24 +0000 Subject: r13658: More moving around of files: - Collect the generic utility functions into a lib/util/ (a la GLib is for the GNOME folks) - Remove even more files from include/ (This used to be commit ba62880f5b05c2a505dc7f54676b231197a7e707) --- source4/lib/util/xfile.c | 384 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 384 insertions(+) create mode 100644 source4/lib/util/xfile.c (limited to 'source4/lib/util/xfile.c') diff --git a/source4/lib/util/xfile.c b/source4/lib/util/xfile.c new file mode 100644 index 0000000000..794e3f0f5e --- /dev/null +++ b/source4/lib/util/xfile.c @@ -0,0 +1,384 @@ +/* + Unix SMB/CIFS implementation. + stdio replacement + Copyright (C) Andrew Tridgell 2001 + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +*/ + +/* + stdio is very convenient, but on some systems the file descriptor + in FILE* is 8 bits, so it fails when more than 255 files are open. + + XFILE replaces stdio. It is less efficient, but at least it works + when you have lots of files open + + The main restriction on XFILE is that it doesn't support seeking, + and doesn't support O_RDWR. That keeps the code simple. +*/ + +#include "includes.h" +#include "system/filesys.h" + +#define XBUFSIZE BUFSIZ + +static XFILE _x_stdin = { 0, NULL, NULL, XBUFSIZE, 0, O_RDONLY, X_IOFBF, 0 }; +static XFILE _x_stdout = { 1, NULL, NULL, XBUFSIZE, 0, O_WRONLY, X_IOLBF, 0 }; +static XFILE _x_stderr = { 2, NULL, NULL, 0, 0, O_WRONLY, X_IONBF, 0 }; + +XFILE *x_stdin = &_x_stdin; +XFILE *x_stdout = &_x_stdout; +XFILE *x_stderr = &_x_stderr; + +#define X_FLAG_EOF 1 +#define X_FLAG_ERROR 2 +#define X_FLAG_EINVAL 3 + +/* simulate setvbuf() */ +int x_setvbuf(XFILE *f, char *buf, int mode, size_t size) +{ + x_fflush(f); + if (f->bufused) return -1; + + /* on files being read full buffering is the only option */ + if ((f->open_flags & O_ACCMODE) == O_RDONLY) { + mode = X_IOFBF; + } + + /* destroy any earlier buffer */ + SAFE_FREE(f->buf); + f->buf = 0; + f->bufsize = 0; + f->next = NULL; + f->bufused = 0; + f->buftype = mode; + + if (f->buftype == X_IONBF) return 0; + + /* if buffering then we need some size */ + if (size == 0) size = XBUFSIZE; + + f->bufsize = size; + f->bufused = 0; + + return 0; +} + +/* allocate the buffer */ +static int x_allocate_buffer(XFILE *f) +{ + if (f->buf) return 1; + if (f->bufsize == 0) return 0; + f->buf = malloc(f->bufsize); + if (!f->buf) return 0; + f->next = f->buf; + return 1; +} + + +/* this looks more like open() than fopen(), but that is quite deliberate. + I want programmers to *think* about O_EXCL, O_CREAT etc not just + get them magically added +*/ +XFILE *x_fopen(const char *fname, int flags, mode_t mode) +{ + XFILE *ret; + + ret = malloc_p(XFILE); + if (!ret) return NULL; + + memset(ret, 0, sizeof(XFILE)); + + if ((flags & O_ACCMODE) == O_RDWR) { + /* we don't support RDWR in XFILE - use file + descriptors instead */ + errno = EINVAL; + return NULL; + } + + ret->open_flags = flags; + + ret->fd = open(fname, flags, mode); + if (ret->fd == -1) { + SAFE_FREE(ret); + return NULL; + } + + x_setvbuf(ret, NULL, X_IOFBF, XBUFSIZE); + + return ret; +} + +/* simulate fclose() */ +int x_fclose(XFILE *f) +{ + int ret; + + /* make sure we flush any buffered data */ + x_fflush(f); + + ret = close(f->fd); + f->fd = -1; + if (f->buf) { + /* make sure data can't leak into a later malloc */ + memset(f->buf, 0, f->bufsize); + SAFE_FREE(f->buf); + } + /* check the file descriptor given to the function is NOT one of the static + * descriptor of this libreary or we will free unallocated memory + * --sss */ + if (f != x_stdin && f != x_stdout && f != x_stderr) { + SAFE_FREE(f); + } + return ret; +} + +/* simulate fwrite() */ +size_t x_fwrite(const void *p, size_t size, size_t nmemb, XFILE *f) +{ + ssize_t ret; + size_t total=0; + + /* we might be writing unbuffered */ + if (f->buftype == X_IONBF || + (!f->buf && !x_allocate_buffer(f))) { + ret = write(f->fd, p, size*nmemb); + if (ret == -1) return -1; + return ret/size; + } + + + while (total < size*nmemb) { + size_t n = f->bufsize - f->bufused; + n = MIN(n, (size*nmemb)-total); + + if (n == 0) { + /* it's full, flush it */ + x_fflush(f); + continue; + } + + memcpy(f->buf + f->bufused, total+(const char *)p, n); + f->bufused += n; + total += n; + } + + /* when line buffered we need to flush at the last linefeed. This can + flush a bit more than necessary, but that is harmless */ + if (f->buftype == X_IOLBF && f->bufused) { + int i; + for (i=(size*nmemb)-1; i>=0; i--) { + if (*(i+(const char *)p) == '\n') { + x_fflush(f); + break; + } + } + } + + return total/size; +} + +/* thank goodness for asprintf() */ + int x_vfprintf(XFILE *f, const char *format, va_list ap) +{ + char *p; + int len, ret; + va_list ap2; + + VA_COPY(ap2, ap); + + len = vasprintf(&p, format, ap2); + if (len <= 0) return len; + ret = x_fwrite(p, 1, len, f); + SAFE_FREE(p); + return ret; +} + + int x_fprintf(XFILE *f, const char *format, ...) +{ + va_list ap; + int ret; + + va_start(ap, format); + ret = x_vfprintf(f, format, ap); + va_end(ap); + return ret; +} + +/* at least fileno() is simple! */ +int x_fileno(XFILE *f) +{ + return f->fd; +} + +/* simulate fflush() */ +int x_fflush(XFILE *f) +{ + int ret; + + if (f->flags & X_FLAG_ERROR) return -1; + + if ((f->open_flags & O_ACCMODE) != O_WRONLY) { + errno = EINVAL; + return -1; + } + + if (f->bufused == 0) return 0; + + ret = write(f->fd, f->buf, f->bufused); + if (ret == -1) return -1; + + f->bufused -= ret; + if (f->bufused > 0) { + f->flags |= X_FLAG_ERROR; + memmove(f->buf, ret + (char *)f->buf, f->bufused); + return -1; + } + + return 0; +} + +/* simulate setbuffer() */ +void x_setbuffer(XFILE *f, char *buf, size_t size) +{ + x_setvbuf(f, buf, buf?X_IOFBF:X_IONBF, size); +} + +/* simulate setbuf() */ +void x_setbuf(XFILE *f, char *buf) +{ + x_setvbuf(f, buf, buf?X_IOFBF:X_IONBF, XBUFSIZE); +} + +/* simulate setlinebuf() */ +void x_setlinebuf(XFILE *f) +{ + x_setvbuf(f, NULL, X_IOLBF, 0); +} + + +/* simulate feof() */ +int x_feof(XFILE *f) +{ + if (f->flags & X_FLAG_EOF) return 1; + return 0; +} + +/* simulate ferror() */ +int x_ferror(XFILE *f) +{ + if (f->flags & X_FLAG_ERROR) return 1; + return 0; +} + +/* fill the read buffer */ +static void x_fillbuf(XFILE *f) +{ + int n; + + if (f->bufused) return; + + if (!f->buf && !x_allocate_buffer(f)) return; + + n = read(f->fd, f->buf, f->bufsize); + if (n <= 0) return; + f->bufused = n; + f->next = f->buf; +} + +/* simulate fgetc() */ +int x_fgetc(XFILE *f) +{ + int ret; + + if (f->flags & (X_FLAG_EOF | X_FLAG_ERROR)) return EOF; + + if (f->bufused == 0) x_fillbuf(f); + + if (f->bufused == 0) { + f->flags |= X_FLAG_EOF; + return EOF; + } + + ret = *(uint8_t *)(f->next); + f->next++; + f->bufused--; + return ret; +} + +/* simulate fread */ +size_t x_fread(void *p, size_t size, size_t nmemb, XFILE *f) +{ + size_t total = 0; + while (total < size*nmemb) { + int c = x_fgetc(f); + if (c == EOF) break; + (total+(char *)p)[0] = (char)c; + total++; + } + return total/size; +} + +/* simulate fgets() */ +char *x_fgets(char *s, int size, XFILE *stream) +{ + char *s0 = s; + int l = size; + while (l>1) { + int c = x_fgetc(stream); + if (c == EOF) break; + *s++ = (char)c; + l--; + if (c == '\n') break; + } + if (l==size || x_ferror(stream)) { + return 0; + } + *s = 0; + return s0; +} + +/* trivial seek, works only for SEEK_SET and SEEK_END if SEEK_CUR is + * set then an error is returned */ +off_t x_tseek(XFILE *f, off_t offset, int whence) +{ + if (f->flags & X_FLAG_ERROR) + return -1; + + /* only SEEK_SET and SEEK_END are supported */ + /* SEEK_CUR needs internal offset counter */ + if (whence != SEEK_SET && whence != SEEK_END) { + f->flags |= X_FLAG_EINVAL; + errno = EINVAL; + return -1; + } + + /* empty the buffer */ + switch (f->open_flags & O_ACCMODE) { + case O_RDONLY: + f->bufused = 0; + break; + case O_WRONLY: + if (x_fflush(f) != 0) + return -1; + break; + default: + errno = EINVAL; + return -1; + } + + f->flags &= ~X_FLAG_EOF; + return lseek(f->fd, offset, whence); +} -- cgit