uncast.c

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	 * Actually, loop-unrolling was done here: you can combine them together but...
	 */
	if (easysearch)
	{	/* compress was done in a context-free way to speed up searches */
		while(1) {
			if((c = mygetc(infp, inbuf, maxinlen, &inlen)) == MYEOF) return outlen;

		bypass_getc1:
			if (c == ONE_VERBATIM) {
				if ((maxoutlen >= 0) && (outlen + 1 >= maxoutlen)) return outlen;
				if ((c = mygetc(infp, inbuf, maxinlen, &inlen)) == MYEOF) return outlen;
				if (outfp != NULL) putc(c, outfp);	/* no processing whatsoever */
				if (outbuf != NULL) outbuf[outlen] = c;
				outlen ++;
			}
			else if (verbatim_state) {
				if (c == END_VERBATIM) verbatim_state = 0;
				else {
					if ((maxoutlen >= 0) && (outlen + 1 >= maxoutlen)) return outlen;
					if (outfp != NULL) putc(c, outfp);
					if (outbuf != NULL) outbuf[outlen] = c;
					outlen ++;
				}
			}
			else if (c < END_SPECIAL_CHARS) {
				process_special_char(c)
				if ( ((c == NEWLINE) || (c == TWONEWLINES)) && untilnewline)
					return outlen;
			}
			else if (c == BEGIN_VERBATIM) {
				if((c = mygetc(infp, inbuf, maxinlen, &inlen)) == MYEOF) return outlen;
				if ((maxoutlen >= 0) && (outlen + 1>= maxoutlen)) return outlen;
				if (outfp != NULL) putc(c, outfp);
				if (outbuf != NULL) outbuf[outlen] = c;
				outlen ++;
				verbatim_state = 1;
			}
			else if (c == END_VERBATIM) {	/* not in verbatim state, still end_verbatim! */
				verbatim_state = 0;
				fprintf(stderr, "error in decompression after %d chars [verbatim processing]. skipping...\n", inlen);
				UNCAST_ERRORS = 1;
			}
			else
			{
			above1:
				if (c < RESERVED_CHARS) {	/* this is a special-word but not a special char */
					process_special_char(c)
				}
				else {	/* it is an index of a word in the dictionary since 1st byte >= RESERVED_CHARS */
					index = c;
					index <<= 8;
					if ((c = mygetc(infp, inbuf, maxinlen, &inlen)) == MYEOF) return outlen;
					index |= c;
					dindex = decode_index(index);
					if(dindex < MAX_WORDS) {
						if ((maxoutlen >= 0) && (outlen + AVG_WORD_LEN >= maxoutlen)) return outlen;
						if (outfp != NULL) outlen += myfpcopy(outfp, compress_string_table[dindex]);
						if (outbuf != NULL) {
							outlen += mystrcpy(outbuf+outlen, compress_string_table[dindex]);
						}
						if ((maxoutlen >= 0) && (outlen >= maxoutlen)) return outlen;
					}
					else {
						fprintf(stderr, "error in decomperssion after %d chars [bad index %x]. skipping...\n", inlen, index);
						UNCAST_ERRORS = 1;
					}
				}

			/* process_char_after_word1: */
				/* now to see what follows the word: a blank or a special delimiter or not-blank */
				if((c = mygetc(infp, inbuf, maxinlen, &inlen)) == MYEOF) {
					if (!TC_FOUND_NOTBLANK) {
						if (outfp != NULL) putc(' ', outfp);
						if (outbuf != NULL) outbuf[outlen] = ' ';
						outlen ++;
					}
					TC_FOUND_NOTBLANK = 0;	/* default: use result of previous forward_tcompressed_word only */
					return outlen;
				}
				else if (c < MAX_SPECIAL_CHARS) {
					if ((c < END_SPECIAL_DELIMITERS) && (c >= BEGIN_SPECIAL_DELIMITERS)) {
						if ((maxoutlen >= 0) && (outlen + 1 >= maxoutlen)) return outlen;
						if (outfp != NULL) putc(special_delimiters[c - BEGIN_SPECIAL_DELIMITERS], outfp);
						if (outbuf != NULL) outbuf[outlen] = special_delimiters[c - BEGIN_SPECIAL_DELIMITERS];
						outlen ++;
					}
					else if (c != NOTBLANK) {
						if ((maxoutlen >= 0) && (outlen + 1 >= maxoutlen)) return outlen;
						if (outfp != NULL) putc(' ', outfp);
						if (outbuf != NULL) outbuf[outlen] = ' ';
						outlen ++;
						goto bypass_getc1;
					}
					/* else go normal getc */
				}
				else {	/* can be one of the special_words or a dictionary index */
					if ((maxoutlen >= 0) && (outlen + 1 >= maxoutlen)) return outlen;
					if (outfp != NULL) putc(' ', outfp);
					if (outbuf != NULL) outbuf[outlen] = ' ';
					outlen ++;
					goto above1;
				}
			}
		}
	}
	else
	{	/* compression was done in a context sensitive fashion w/o regards to search */
		while(1) {
			if((c = mygetc(infp, inbuf, maxinlen, &inlen)) == MYEOF) return outlen;

		bypass_getc2:
			if (verbatim_state) {
				if (c == END_VERBATIM) verbatim_state = 0;
				else if (c == BEGIN_VERBATIM) goto verbatim_processing;
				else {
					if ((maxoutlen >= 0) && (outlen + 1 >= maxoutlen)) return outlen;
					if (outfp != NULL) putc(c, outfp);
					if (outbuf != NULL) outbuf[outlen] = c;
					outlen ++;
				}
			}
			else if (c < END_SPECIAL_CHARS) {
				process_special_char(c)
				if ( ((c == NEWLINE) || (c == TWONEWLINES)) && untilnewline)
				return outlen;
			}
			else if (c == BEGIN_VERBATIM) {
			verbatim_processing:
				if ((maxoutlen >= 0) && (outlen + 1 >= maxoutlen)) return outlen;
				if((c = mygetc(infp, inbuf, maxinlen, &inlen)) == MYEOF) return outlen;
				if (outfp != NULL) putc(c, outfp);
				if (outbuf != NULL) outbuf[outlen] = c;
				outlen ++;
				if ((c!=BEGIN_VERBATIM) && (c!=END_VERBATIM)) verbatim_state = 1;	/* only _these_ are escape characters */
			}
			else if (c == END_VERBATIM) {	/* not in verbatim state, still end_verbatim! */
				verbatim_state = 0;
				fprintf(stderr, "error in decompression after %d chars [verbatim processing]. skipping...\n", inlen);
				UNCAST_ERRORS = 1;
			}
			else
			{
			above2:
				if (c < RESERVED_CHARS) {	/* this is a special-word but not a special char */
					process_special_char(c)
				}
				else {	/* it is an index of a word in the dictionary since 1st byte >= RESERVED_CHARS */
					index = c;
					index <<= 8;
					if ((c = mygetc(infp, inbuf, maxinlen, &inlen)) == MYEOF) return outlen;
					index |= c;
					dindex = decode_index(index);
					if(dindex < MAX_WORDS) {
						if ((maxoutlen >= 0) && (outlen + AVG_WORD_LEN >= maxoutlen)) return outlen;
						if (outfp != NULL) outlen += myfpcopy(outfp, compress_string_table[dindex]);
						if (outbuf != NULL) {
							outlen += mystrcpy(outbuf+outlen, compress_string_table[dindex]);
						}
						if ((maxoutlen >= 0) && (outlen >= maxoutlen)) return outlen;
					}
					else {
						fprintf(stderr, "error in decomperssion after %d chars [bad index %x]. skipping...\n", inlen, index);
						UNCAST_ERRORS = 1;
					}
				}

			/* process_char_after_word2: */
				/* now to see what follows the word: a blank or a special delimiter or not-blank */
				if((c = mygetc(infp, inbuf, maxinlen, &inlen)) == MYEOF) {
					if (!TC_FOUND_NOTBLANK) {
						if (outfp != NULL) putc(' ', outfp);
						if (outbuf != NULL) outbuf[outlen] = ' ';
						outlen ++;
					}
					TC_FOUND_NOTBLANK = 0;	/* default: use result of previous forward_tcompressed_word only */
					return outlen;
				}
				else if (c < MAX_SPECIAL_CHARS) {
					if ((c < END_SPECIAL_DELIMITERS) && (c >= BEGIN_SPECIAL_DELIMITERS)) {
						if ((maxoutlen >= 0) && (outlen + 1 >= maxoutlen)) return outlen;
						if (outfp != NULL) putc(special_delimiters[c - BEGIN_SPECIAL_DELIMITERS], outfp);
						if (outbuf != NULL) outbuf[outlen] = special_delimiters[c - BEGIN_SPECIAL_DELIMITERS];
						outlen ++;
					}
					else if (c != NOTBLANK) {
						if ((maxoutlen >= 0) && (outlen + 1 >= maxoutlen)) return outlen;
						if (outfp != NULL) putc(' ', outfp);
						if (outbuf != NULL) outbuf[outlen] = ' ';
						outlen ++;
						goto bypass_getc2;
					}
					/* else go normal getc */
				}
				else {	/* can be one of the special_words or a dictionary index */
					if ((maxoutlen >= 0) && (outlen + 1 >= maxoutlen)) return outlen;
					if (outfp != NULL) putc(' ', outfp);
					if (outbuf != NULL) outbuf[outlen] = ' ';
					outlen ++;
					goto above2;
				}
			}
		}
	}
}

#define FUNCTION	tuncompress_file
#define DIRECTORY	tuncompress_directory
#include "trecursive.c"

/* returns #bytes (>=0) in the uncompressed file, -1 if major error (not able to uncompress) */
int
tuncompress_file(name, outname, flags)
	char	*name;
	char	*outname;
	int	flags;
{
	FILE	*fp;
	FILE	*outfp;
	int	inlen, ret;
	struct stat statbuf;
	/* struct timeval tvp[2]; */
	struct utimbuf tvp;
	char	tempname[MAX_LINE_LEN];

	if (name == NULL) return -1;
	special_get_name(name, -1, tempname);

	if (-1 == stat(tempname, &statbuf)) {
		if (flags & TC_ERRORMSGS)
			fprintf(stderr, "permission denied or non-existent: %s\n", tempname);
		return -1;
	}
	if (S_ISDIR(statbuf.st_mode)) {
		if (flags & TC_RECURSIVE) return tuncompress_directory(tempname, outname, flags);
		if (flags & TC_ERRORMSGS)
			fprintf(stderr, "skipping directory: %s\n", tempname);
		return -1;
	}
        if (!S_ISREG(statbuf.st_mode)) {
                if (flags & TC_ERRORMSGS)
			fprintf(stderr, "not a regular file, skipping: %s\n", tempname);
                return -1;
	}

	inlen = strlen(tempname);
	if (!tuncompressible_filename(tempname, inlen)) {
		if (!(flags & TC_RECURSIVE) && (flags & TC_ERRORMSGS))
			fprintf(stderr, "no %s extension, skipping: %s\n", COMP_SUFFIX, tempname);
		return -1;
	}
	if ((fp = fopen(tempname, "r")) == NULL) {
		if (flags & TC_ERRORMSGS)
			fprintf(stderr, "permission denied or non-existent: %s\n", tempname);
		return -1;
	}
	if (!tuncompressible_fp(fp)) {
		if (flags & TC_ERRORMSGS)
			fprintf(stderr, "signature does not match, skipping: %s\n", tempname);
		fclose(fp);
		return -1;
	}
	if (flags & TC_SILENT) {
		printf("%s\n", tempname);
		fclose(fp);
		return 0;
	}

	/* Create and open output file */
	strncpy(outname, tempname, MAX_LINE_LEN);
	outname[inlen - strlen(COMP_SUFFIX)] = '\0';
	if (!access(outname, R_OK)) {
		if (!(flags & TC_OVERWRITE)) {
			fclose(fp);
			return 0;
		}
		else if (!(flags & TC_NOPROMPT)) {
			char	s[8];
			printf("overwrite %s? (y/n): ", outname);
			scanf("%c", s);
			if (s[0] != 'y') {
				fclose(fp);
				return 0;
			}
		}
	}
	if ((outfp = fopen(outname, "w")) == NULL) {
		if (flags & TC_ERRORMSGS)
			fprintf(stderr, "cannot open for writing: %s\n", outname);
		fclose(fp);
		return -1;
	}

	UNCAST_ERRORS = 0;
	if ( ((ret = tuncompress(fp, -1, outfp, -1, flags)) > 0) && !UNCAST_ERRORS && (flags & TC_REMOVE)) {
		unlink(tempname);
	}

	fclose(fp);
	fflush(outfp);
	fclose(outfp);
	/*
	tvp[0].tv_sec = statbuf.st_atime;
	tvp[0].tv_usec = 0;
	tvp[1].tv_sec = statbuf.st_mtime;
	tvp[1].tv_usec = 0;
	utimes(outname, tvp);
	*/
	tvp.actime = statbuf.st_atime;
	tvp.modtime = statbuf.st_mtime;
	utime(outname, &tvp);
	return ret;
}