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debug
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imap-2007f
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c-client
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Filename :
fdstring.c
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/* ======================================================================== * Copyright 1988-2007 University of Washington * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * * ======================================================================== */ /* * Program: File descriptor string routines * * Author: Mark Crispin * Networks and Distributed Computing * Computing & Communications * University of Washington * Administration Building, AG-44 * Seattle, WA 98195 * Internet: MRC@CAC.Washington.EDU * * Date: 15 April 1997 * Last Edited: 4 April 2007 */ #include "mail.h" #include "osdep.h" #include "misc.h" #include "fdstring.h" /* String driver for fd stringstructs */ static void fd_string_init (STRING *s,void *data,unsigned long size); static char fd_string_next (STRING *s); static void fd_string_setpos (STRING *s,unsigned long i); STRINGDRIVER fd_string = { fd_string_init, /* initialize string structure */ fd_string_next, /* get next byte in string structure */ fd_string_setpos /* set position in string structure */ }; /* Initialize string structure for fd stringstruct * Accepts: string structure * pointer to string * size of string */ static void fd_string_init (STRING *s,void *data,unsigned long size) { FDDATA *d = (FDDATA *) data; /* note fd */ s->data = (void *) (unsigned long) d->fd; s->data1 = d->pos; /* note file offset */ s->size = size; /* note size */ s->curpos = s->chunk = d->chunk; s->chunksize = (unsigned long) d->chunksize; s->offset = 0; /* initial position */ /* and size of data */ s->cursize = min (s->chunksize,size); /* move to that position in the file */ lseek (d->fd,d->pos,L_SET); read (d->fd,s->chunk,(size_t) s->cursize); } /* Get next character from fd stringstruct * Accepts: string structure * Returns: character, string structure chunk refreshed */ static char fd_string_next (STRING *s) { char c = *s->curpos++; /* get next byte */ SETPOS (s,GETPOS (s)); /* move to next chunk */ return c; /* return the byte */ } /* Set string pointer position for fd stringstruct * Accepts: string structure * new position */ static void fd_string_setpos (STRING *s,unsigned long i) { if (i > s->size) i = s->size; /* don't permit setting beyond EOF */ s->offset = i; /* set new offset */ s->curpos = s->chunk; /* reset position */ /* set size of data */ if (s->cursize = min (s->chunksize,SIZE (s))) { /* move to that position in the file */ lseek ((long) s->data,s->data1 + s->offset,L_SET); read ((long) s->data,s->curpos,(size_t) s->cursize); } }