diff options
Diffstat (limited to 'gs/base/sbcp.c')
| -rw-r--r-- | gs/base/sbcp.c | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/gs/base/sbcp.c b/gs/base/sbcp.c new file mode 100644 index 000000000..169968b74 --- /dev/null +++ b/gs/base/sbcp.c @@ -0,0 +1,248 @@ +/* Copyright (C) 2001-2006 Artifex Software, Inc. + All Rights Reserved. + + This software is provided AS-IS with no warranty, either express or + implied. + + This software is distributed under license and may not be copied, modified + or distributed except as expressly authorized under the terms of that + license. Refer to licensing information at http://www.artifex.com/ + or contact Artifex Software, Inc., 7 Mt. Lassen Drive - Suite A-134, + San Rafael, CA 94903, U.S.A., +1(415)492-9861, for further information. +*/ + +/* $Id$ */ +/* BCP and TBCP filters */ +#include "stdio_.h" +#include "strimpl.h" +#include "sbcp.h" + +#define CtrlA 0x01 +#define CtrlC 0x03 +#define CtrlD 0x04 +#define CtrlE 0x05 +#define CtrlQ 0x11 +#define CtrlS 0x13 +#define CtrlT 0x14 +#define ESC 0x1b +#define CtrlBksl 0x1c + +/* The following is not used yet. */ +/*static const char *TBCP_end_protocol_string = "\033%-12345X";*/ + +/* ------ BCPEncode and TBCPEncode ------ */ + +/* Process a buffer */ +static int +s_xBCPE_process(stream_state * st, stream_cursor_read * pr, + stream_cursor_write * pw, bool last, const byte * escaped) +{ + const byte *p = pr->ptr; + const byte *rlimit = pr->limit; + uint rcount = rlimit - p; + byte *q = pw->ptr; + uint wcount = pw->limit - q; + const byte *end = p + min(rcount, wcount); + + while (p < end) { + byte ch = *++p; + + if (ch <= 31 && escaped[ch]) { + if (p == rlimit) { + p--; + break; + } + *++q = CtrlA; + ch ^= 0x40; + if (--wcount < rcount) + end--; + } + *++q = ch; + } + pr->ptr = p; + pw->ptr = q; + return (p == rlimit ? 0 : 1); +} + +/* Actual process procedures */ +static int +s_BCPE_process(stream_state * st, stream_cursor_read * pr, + stream_cursor_write * pw, bool last) +{ + static const byte escaped[32] = + { + 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0 + }; + + return s_xBCPE_process(st, pr, pw, last, escaped); +} +static int +s_TBCPE_process(stream_state * st, stream_cursor_read * pr, + stream_cursor_write * pw, bool last) +{ + static const byte escaped[32] = + { + 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0 + }; + + return s_xBCPE_process(st, pr, pw, last, escaped); +} + +/* Stream templates */ +const stream_template s_BCPE_template = +{&st_stream_state, NULL, s_BCPE_process, 1, 2 +}; +const stream_template s_TBCPE_template = +{&st_stream_state, NULL, s_TBCPE_process, 1, 2 +}; + +/* ------ BCPDecode and TBCPDecode ------ */ + +private_st_BCPD_state(); + +/* Initialize the state */ +static int +s_BCPD_init(stream_state * st) +{ + stream_BCPD_state *const ss = (stream_BCPD_state *) st; + + ss->escaped = 0; + ss->matched = ss->copy_count = 0; + return 0; +} + +/* Process a buffer */ +static int +s_xBCPD_process(stream_state * st, stream_cursor_read * pr, + stream_cursor_write * pw, bool last, bool tagged) +{ + stream_BCPD_state *const ss = (stream_BCPD_state *) st; + const byte *p = pr->ptr; + const byte *rlimit = pr->limit; + byte *q = pw->ptr; + byte *wlimit = pw->limit; + int copy_count = ss->copy_count; + int status; + bool escaped = ss->escaped; + + for (;;) { + byte ch; + + if (copy_count) { + if (q == wlimit) { + status = (p < rlimit ? 1 : 0); + break; + } + *++q = *++(ss->copy_ptr); + copy_count--; + continue; + } + if (p == rlimit) { + status = 0; + break; + } + ch = *++p; + if (ch <= 31) + switch (ch) { + case CtrlA: + if (escaped) { + status = ERRC; + goto out; + } + escaped = true; + continue; + case CtrlC: + status = (*ss->signal_interrupt) (st); + if (status < 0) + goto out; + continue; + case CtrlD: + if (escaped) { + status = ERRC; + goto out; + } + status = EOFC; + goto out; + case CtrlE: + continue; + case CtrlQ: + continue; + case CtrlS: + continue; + case CtrlT: + status = (*ss->request_status) (st); + if (status < 0) + goto out; + continue; + case CtrlBksl: + continue; + } + if (q == wlimit) { + p--; + status = 1; + break; + } + if (escaped) { + escaped = false; + switch (ch) { + case '[': + if (!tagged) { + status = ERRC; + goto out; + } + /* falls through */ + case 'A': + case 'C': + case 'D': + case 'E': + case 'Q': + case 'S': + case 'T': + case '\\': + ch ^= 0x40; + break; + case 'M': + if (!tagged) { + status = ERRC; + goto out; + } + continue; + default: + status = ERRC; + goto out; + } + } + *++q = ch; + } + out:ss->copy_count = copy_count; + ss->escaped = escaped; + pr->ptr = p; + pw->ptr = q; + return status; +} + +/* Actual process procedures */ +static int +s_BCPD_process(stream_state * st, stream_cursor_read * pr, + stream_cursor_write * pw, bool last) +{ + return s_xBCPD_process(st, pr, pw, last, false); +} +static int +s_TBCPD_process(stream_state * st, stream_cursor_read * pr, + stream_cursor_write * pw, bool last) +{ + return s_xBCPD_process(st, pr, pw, last, true); +} + +/* Stream templates */ +const stream_template s_BCPD_template = +{&st_BCPD_state, s_BCPD_init, s_BCPD_process, 1, 1, + NULL, NULL, s_BCPD_init +}; +const stream_template s_TBCPD_template = +{&st_BCPD_state, s_BCPD_init, s_TBCPD_process, 1, 1, + NULL, NULL, s_BCPD_init +}; |