/* $Id: pushback.c,v 1.2 2000/12/14 18:45:35 ghazi Exp $ $Log: pushback.c,v $ Revision 1.2 2000/12/14 18:45:35 ghazi Warning fixes: * compress.c: Include stdlib.h and compress.h. (rcsid): Delete. (report_str_error): Make static. (ez_inflate_str): Delete unused variable. Add parens in if-stmt. (hrd_inflate_str): Likewise. * compress.h (init_compression, end_compression, init_inflation, end_inflation): Prototype void arguments. * dostime.c (rcsid): Delete. * jargrep.c: Include ctype.h, stdlib.h, zlib.h and compress.h. Make functions static. Cast ctype function argument to `unsigned char'. Add parens in if-stmts. Constify. (Usage): Change into a macro. (jargrep): Remove unused parameter. * jartool.c: Constify. Add parens in if-stmts. Align signed/unsigned char pointers in functions calls using casts. (rcsid): Delete. (list_jar): Fix printf format specifier. (usage): Chop long string into bits. Reformat. * pushback.c (rcsid): Delete. Revision 1.1 2000/12/09 03:08:23 apbianco 2000-12-08 Alexandre Petit-Bianco * fastjar: Imported. Revision 1.2 2000/08/23 19:42:17 cory Added support for more Unix platforms. The following code has been hacked to work on AIX, Solaris, True 64, and HP-UX. Added bigendian check. Probably works on most big and little endian platforms now. Revision 1.1.1.1 1999/12/06 03:09:13 toast initial checkin.. Revision 1.1 1999/05/10 08:32:37 burnsbr Initial revision */ /* pushback.c - code for a pushback buffer to handle file I/O Copyright (C) 1999 Bryan Burns 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include #include #include #include "jartool.h" #include "pushback.h" void pb_init(pb_file *pbf, int fd){ pbf->fd = fd; pbf->next = pbf->pb_buff; pbf->buff_amt = 0; } int pb_push(pb_file *pbf, void *buff, int amt){ int in_amt; int wrap = 0; #ifdef DEBUG printf("%d bytes being pushed back to the buffer\n", amt); #endif /* determine how much we can take */ if((int)(RDSZ - pbf->buff_amt) < amt) in_amt = RDSZ - pbf->buff_amt; else in_amt = amt; if(in_amt == 0) return 0; /* figure out if we need to wrap around, and if so, by how much */ if(((pbf->pb_buff + RDSZ) - pbf->next) < in_amt) wrap = in_amt - ((pbf->pb_buff + RDSZ) - pbf->next); /* write everything up til the end of the buffer */ memcpy(pbf->next, buff, (in_amt - wrap)); /* finish writing what's wrapped around */ memcpy(pbf->pb_buff, ((char *)buff + (in_amt - wrap)), wrap); /* update the buff_amt field */ pbf->buff_amt += in_amt; #ifdef DEBUG printf("%d bytes we can't accept\n", (amt - in_amt)); #endif return in_amt; } int pb_read(pb_file *pbf, void *buff, int amt){ int out_amt = 0; int wrap = 0; void *bp = buff; int tmp; #ifdef DEBUG printf("%d bytes requested from us\n", amt); #endif while(out_amt < amt){ /* if our push-back buffer contains some data */ if(pbf->buff_amt > 0){ #ifdef DEBUG printf("giving data from buffer\n"); #endif /* calculate how much we can actually give the caller */ if( (amt - out_amt) < (int)pbf->buff_amt ) tmp = (amt - out_amt); else tmp = pbf->buff_amt; /* Determine if we're going to need to wrap around the buffer */ if(tmp > ((pbf->pb_buff + RDSZ) - pbf->next)) wrap = tmp - ((pbf->pb_buff + RDSZ) - pbf->next); memcpy(bp, pbf->next, (tmp - wrap)); bp = &(((char *)bp)[tmp - wrap]); /* If we need to wrap, read from the start of the buffer */ if(wrap > 0){ memcpy(bp, pbf->pb_buff, wrap); bp = &(((char *)bp)[wrap]); } /* update the buff_amt field */ pbf->buff_amt -= tmp; pbf->next += tmp; #ifdef DEBUG printf("%d bytes remaining in buffer\n", pbf->buff_amt); #endif /* if the buffer is empty, reset the next header to the front of the buffer so subsequent pushbacks/reads won't have to wrap */ if(pbf->buff_amt == 0) pbf->next = pbf->pb_buff; out_amt += tmp; } else { #ifdef DEBUG printf("Reading from file..\n"); #endif /* The pushback buffer was empty, so we just need to read from the file */ tmp = read(pbf->fd, bp, (amt - out_amt)); if(tmp == 0) break; else out_amt += tmp; bp = &(((char *)bp)[tmp]); } } #ifdef DEBUG printf("managed to read %d bytes\n", out_amt); #endif return out_amt; }