pass3.c

操作系统源代码

/*
 *	pass3.c - cawf(1) pass 3 function
 */

/*
 *	Copyright (c) 1991 Purdue University Research Foundation,
 *	West Lafayette, Indiana 47907.  All rights reserved.
 *
 *	Written by Victor A. Abell <[e-mail]>,  Purdue
 *	University Computing Center.  Not derived from licensed software;
 *	derived from awf(1) by Henry Spencer of the University of Toronto.
 *
 *	Permission is granted to anyone to use this software for any
 *	purpose on any computer system, and to alter it and redistribute
 *	it freely, subject to the following restrictions:
 *
 *	1. The author is not responsible for any consequences of use of
 *	   this software, even if they arise from flaws in it.
 *
 *	2. The origin of this software must not be misrepresented, either
 *	   by explicit claim or by omission.  Credits must appear in the
 *	   documentation.
 *
 *	3. Altered versions must be plainly marked as such, and must not
 *	   be misrepresented as being the original software.  Credits must
 *	   appear in the documentation.
 *
 *	4. This notice may not be removed or altered.
 */

#include "cawf.h"

void
Pass3(len, word, sarg, narg)
	int len;			/* length (negative is special) */
	unsigned char *word;		/* word */
	unsigned char *sarg;		/* string argument */
	int narg;			/* numeric argument */
{
	int addto;			/* spaces to add to all words */
	int i, j, k;			/* temporary index */
	unsigned char msg[MAXLINE];	/* message buffer */
	int n;				/* temporary number */
	unsigned char *s1;		/* temporary string pointer */
	int sp = 0;			/* no-break spacing switch */
	int sp_Outll;			/* sp-saved Outll */
	char sp_Outln;			/* sp-saved Outln[0] */
	int sp_Outlx;			/* sp-saved Outlx */
	int sp_Padx;			/* sp-saved Padx */
	int sp_Tind;			/* sp-saved Tind */
	int wl;				/* real word length */
	int xsp;			/* extra spaces to add */
	int vsp;			/* vertical spacing status */

	vsp = 0;
	if (word != NULL)
		wl = strlen((char *)word);
    /*
     * If not a special command, process a word.
     */
	if (len >= 0 && Outll < 0) {
	/*
	 * Enter first word.
	 */
		(void) strcpy((char *)Outln, (char *)word);
		Outll = len;
		Outlx = wl;
		Padx = 0;
	} else if (len >= 0
	       && (Outll+Contlen+len+narg) <= (LL-Pgoff-Ind-Tind)) {
	/*
	 * The word fits, so enter it.
	 */
		if ((Contlen + len) > 0) {
line_too_big:
			if ((Outlx + Contlen + wl) >= MAXOLL) {
				Error3(len, (char *)word, (char *)sarg, narg,
					"output line too big");
				return;
			} else {
				if (Contlen > 0 && Cont != NULL) {
					if (Contlen == 1 && *Cont == ' ') {
						Padchar[Padx++] = Outlx;
						Outln[Outlx++] = ' ';
					} else {
					    (void) strcpy((char *)&Outln[Outlx],
						(char *)Cont);
					    Outlx += Contlen;
					}
				}
				if (len > 0) {
					(void) strcpy((char *)&Outln[Outlx],
						(char *)word);
					Outlx += wl;
				}
			}
		}
		Outll += Contlen + len;
	} else if (len == NOBREAK || len == MESSAGE) {
		/*
		 * Do nothing (equivalent to break)
		 */
	} else if (len == DOBREAK && strcmp((char *)word, "need") == 0
	       &&  (Nxtln + narg) < (Pglen + 1 - Botmarg)) {
		/*
		 * Do nothing, because there is room on the page.
		 */
	} else if (len == DOBREAK && strcmp((char *)word, "toindent") == 0
	       &&  (Ind + Tind + Outll) < Ind) {
	/*
	 * Move to indent position with line - there is room.
	 */
		n = Ind - (Ind + Tind +Outll);
		Outll += n;
		if ((Outlx + n) >= MAXOLL)
			goto line_too_big;
		for (i = n; i; i--)
			Outln[Outlx++] = ' ';
		Padx = 0;
		Free(&Cont);
		Contlen = 0;
	} else if (Outll >= 0
	       || (len == DOBREAK && strcmp((char *)word, "need") == 0)) {
	/*
	 * A non-empty line or a "need" forces output.
	 */
		vsp = 0;

print_line:
		if (Nxtln == 1) {
	    /*
	     * We're at the top of the page, so issue the header.
	     */
			if (Thispg > 1)
				Charput((int)'\f');
			for (i = (Topmarg - 1)/2; i > 0; i--) {
				Charput((int)'\n');
				Nxtln++;
			}
		    /*
		     * Print the page header, as required.
		     */
			if (Fph || Thispg > 1) {
				i = LenprtHF(Hdc, Thispg, 0)
				  + LenprtHF(Hdl, Thispg, 0)
				  + LenprtHF(Hdr, Thispg, 0) + 2;
				j = (LL - i - Pgoff) / 2 + 1;
				n = LL - Pgoff - i - j + 2;
				for (k = 0; k < Pgoff; k++)
					Charput((int)' ');
				if (Hdl)
					LenprtHF(Hdl, Thispg, 1);
				while (j--)
					Charput((int)' ');
				if (Hdc)
					LenprtHF(Hdc, Thispg, 1);
				while (n--)
					Charput((int)' ');
				if (Hdr)
					LenprtHF(Hdr, Thispg, 1);
				Charput((int)'\n');
			} else
				Charput((int)'\n');
			Nxtln++;
			while(Nxtln <= Topmarg) {
				Charput((int)'\n');
				Nxtln++;
			}
		}
	    /*
	     *  Add a trailing hyphen, if mecessary.
	     */
     		if (vsp == 0 && Eollen > 0 && Eol != NULL) {
			i = strlen((char *)Eol);
			if ((Outlx + i) >= MAXOLL)
				goto line_too_big;
			(void) strcpy((char *)&Outln[Outlx], (char *)Eol);
			Outlx += i;
			Outll += Eollen;
		}
	    /*
	     * Trim trailing spaces from the output line.
	     */
     		while (Outlx > 0) {
			if (Outln[Outlx - 1] != ' ')
				break;
			if (Padx > 0 && (Outlx - 1) == Padchar[Padx - 1])
				Padx--;
			Outlx--;
			Outln[Outlx] = '\0';
			Outll--;
		}
		if (Outlx == 0)
			Charput((int)'\n');
		else if (len == DOBREAK && strcmp((char *)word, "center") == 0)
		    {
		    /*
		     * Center the output line.
		     */
			i = (LL - Pgoff - Outll) / 2;
			if (i < 0)
				i = 0;
			for (j = (Pgoff + Ind + Tind + i); j; j--)
				Charput((int)' ');
			Stringput(Outln);
			Charput((int)'\n');
		} else if (Adj == LEFTADJ
		       || (Adj == BOTHADJ && (len < 0 || Padx == 0))) {
		    /*
		     * No right margin adjustment - disabled, inappropriate
		     * (line ended by break) or impossible.
		     */
			for (i = 0; i < (Pgoff + Ind + Tind); i++)
				Charput((int)' ');
			Stringput(Outln);
			Charput((int)'\n');
		} else if (Adj == BOTHADJ) {
		    /*
		     * Adjust right margin.
		     */
			for (i = 0; i < (Pgoff + Ind + Tind); i++)
				Charput((int)' ');
			i = LL - (Pgoff + Ind + Tind);
			j = i - Outll;
			addto = Padx ? (j / Padx) : 0;
			xsp = j - (Padx * addto);
			for (i = 0, s1 = Outln; i < Padx; i++) {
				while (*s1 && (s1 - Outln) <= Padchar[i])
					Charput((int)*s1++);
				if (*s1 == '\0')
					break;
				j = addto;
				if (Padfrom == PADLEFT) {
					if (i < xsp)
						j++;
				} else if (i >= (Padx - xsp))
					j++;
				while (j--)
					Charput((int)' ');
			}
			while (*s1)
				Charput((int)*s1++);
			Charput((int)'\n');
			Padfrom = (Padfrom == PADLEFT) ? PADRIGHT : PADLEFT;
		}
	    /*
	     * End of line housekeeping
	     */
		Nxtln++;
		Outll = -1;
		Outlx = 0;
		Padx = 0;
		Tind = 0;
		Nospmode = 0;
		if (vsp == 0 && len == DOBREAK
		&&  strcmp((char *)word, "need") == 0) {
		    /*
		     * Break caused by "need" - satisfy it.
		     */
			while (Nxtln < (Pglen + 1 - Botmarg)) {
				Charput((int)'\n');
				Nxtln++;
			}
		}
		if (Nxtln >= (Pglen + 1 - Botmarg)) {
	    /*
	     * Footer required
	     */
			for (i = (Botmarg - 1)/2; i > 0; i--) {
				Charput((int)'\n');
				Nxtln++;
			}
			i = LenprtHF(Ftl, Thispg, 0) + LenprtHF(Ftc, Thispg, 0)
			  + LenprtHF(Ftr, Thispg, 0) + 2;
			j = (LL - i - Pgoff) / 2 + 1;
			n = LL - Pgoff - i - j + 2;
			for (k = 0; k < Pgoff; k++)
				Charput((int)' ');
			if (Ftl)
				LenprtHF(Ftl, Thispg, 1);
			while (j--)
				Charput((int)' ');
			if (Ftc)
				LenprtHF(Ftc, Thispg, 1);
			while (n--)
				Charput((int)' ');
			if (Ftr)
				LenprtHF(Ftr, Thispg, 1);
			Charput((int)'\n');
			Nxtln++;
		/*
		 * The last blank line on the page is suppressed to assist
		 * printers that can't look ahead to the following FF.
		 */
			while (Nxtln < Pglen) {
				Charput((int)'\n');
				Nxtln++;
			}
			Nxtln = 1;
			Thispg++;
			Nospmode = 1;
			Padfrom = PADRIGHT;
		}
	    /*
	     * Initiate any extra vertical spacing.
	     */
		if (++vsp < Vspace)
			goto print_line;
	    /*
	     * Save any input word that might have forced output.
	     */
		if (len >= 0) {
			(void) strcpy((char *)Outln, (char *)word);
			Outll = len;
			Outlx = wl;
			Padx = 0;
		}
	}
    /*
     * A break causes padding reversal.
     */
	if (len == DOBREAK)
		Padfrom = PADRIGHT;
	if (len >= 0 || strcmp((char *)word, "nohyphen") == 0) {
    /*
     * Reset continuation and hyphenation.
     */
		if (Contlen != 1 || Cont[0] != ' ') {
			Free(&Cont);
			Cont = Newstr((unsigned char *)" ");
			Contlen = 1;
		}
		if (Eollen > 0) {
			Free(&Eol);
			Eollen = 0;
		}
		return;
	}
    /*
     * Now post-process any special commands.
     */
	if (len == MESSAGE) {
		Error3(len, (char *)word, (char *)sarg, narg, NULL);
		return;
	}

	switch (*word) {

	case 'b':				/* both */
	    /*
	     * Adjust on both margins.
	     */
		Adj = BOTHADJ;
		return;

	case 'c':				/* center */
		return;

	case 'e':				/* errsto */
	    /*
	     * "errsto" comes from awf.
	     */
		return;

	case 'f':				/* flush and fph */
		if (word[1] == 'l')
			return;
		else if (word[1] == 'p') {
	    /*
	     * First page header status
	     */
			Fph = narg;
			return;
		}
		break;

	case 'g':				/* gap */
	    /*
	     * Increase word gap.  (Space is not paddable.)
	     */
		if (Outll >= 0) {
			if ((Outlx + narg - 1) >= MAXOLL)
				goto line_too_big;
			for (i = 0; i < (narg - 1); i++) {
				Outln[Outlx++] = ' ';
				Outll++;
			}
		}
		return;

	case 'h':				/* hyphen */
	    /*
	     * Set discretionary hyphen.
	     */
		Free(&Cont);
		Contlen = 0;
		Free(&Eol);
		Eol = (sarg != NULL) ? Newstr(sarg) : NULL;
		Eollen = narg;
		return;

	case 'i':				/* indent */
	    /*
	     * Set indentation.
	     */
		Ind = narg;
		return;

	case 'l':				/* left or linelen */
		if (word[1] == 'e') {
	    /*
	     * Adjust on left margin.
	     */
			Adj = LEFTADJ;
			return;
		} else if (word[1] == 'i') {
	    /*
	     * Set line length.
	     */
			LL = narg;
			return;
		}
		break;

	case 'n':				/* need or nospace */
		if (word[1] == 'e')
			return;			/* need */
		else if (word[1] == 'o') {
	    /*
	     * Set no space mode.
	     */
			Nospmode = 1;
			return;
		}
		break;

	case 'p':				/* pagelen or pageoffset */
		if (strncmp((char *)&word[1], "age", 3) != 0)
			break;
		if (word[4] == 'l') {
	    /*
	     * Set page length.
	     */
			Pglen = narg;
			return;
		} else if (word[4] == 'o') {
	    /*
	     * Set page offset.
	     */
			Pgoff = narg;
			return;
		}
		break;

	case 's':				/* space */
		if (sp) {

		/*
		 * Restore values after NOBREAK spacing ("^'sp").
		 */
			Outlx = sp_Outlx;
			Outln[0] = sp_Outln;
			Padx = sp_Padx;
			Outll = sp_Outll;
			Tind = sp_Tind;
			return;
		}
		if (Nospmode == 0) {
			if (len == NOBREAK) {
		
			/*
			 * Set up for NOBREAK spacing.
			 */
				sp_Outlx = Outlx;
				sp_Outln = Outln[0];
				sp_Padx = Padx;
				sp_Outll = Outll;
				sp_Tind = Tind;
				vsp = Vspace + 1;
				sp = 1;
			}
		/*
		 * Generate a blank line.
		 */
			Outlx = 0;
			Outln[0] = '\0';
			Padx = 0;
			Outll = LL - 1;
			if (sp)
				goto print_line;
		}
		return;

	case 't':				/* tabto, tempindent, or
						 * toindent */
		if (word[1] == 'a') {
	    /*
	     * Move to TAB stop.
	     */
			if (Outll < 0)
				Outll = 0;
			if ((n = narg - Outll) > 0) {
				if ((Outlx + n) >= MAXOLL)
					goto line_too_big;
				Outll += n;
				for (i = n; i > 0; i--)
					Outln[Outlx++] = ' ';
				Free(&Cont);
				Contlen = 0;
				Padx = 0;
			}
			return;
		} else if (word[1] == 'e') {
	    /*
	     * Set temporary indentation.
	     */
			if (*sarg == '\0' && narg >= 0)
				Tind = narg - Ind;
			else
				Tind = ((Ind + narg) >= 0) ? narg : -Ind;
			return;
		} else if (word[1] == 'o')
			return;				/* toindent */
		break;

	case 'u':					/* userhyphen */
	    /*
	     * Set line length.
	     */
		Free(&Cont);
		Free(&Eol);
		Contlen = Eollen = narg;
		Cont = (sarg == NULL) ? NULL : Newstr(sarg);
		Eol = (sarg == NULL) ? NULL : Newstr(sarg);
		return;

	case 'v':					/* vspace */
	    /*
	     * Set vertical spacing.
	     */
		Vspace = (narg == 0) ? 1 : narg;
		return;

	case 'y':					/* yesspace */
	    /*
	     * Set space mode.
	     */
		Nospmode = 0;
		return;
	}				/* end of switch(*word) */
    /*
     * Locate header and footer defintions.
     */
	if (regexec(Pat[14].pat, word)) {
		if (strcmp((char *)word, "LH") == 0) {
		    /*
		     * Left header
		     */
			Free(&Hdl);
			if (sarg != NULL)
				Hdl = Newstr(sarg);
			return;
		}
		if (strcmp((char *)word, "CH") == 0) {
		    /*
		     * Center header
		     */
			Free(&Hdc);
			if (sarg != NULL)
				Hdc = Newstr(sarg);
			return;
		}
		if (strcmp((char *)word, "RH") == 0) {
		    /*
		     * Right header
		     */
			Free(&Hdr);
			if (sarg != NULL)
				Hdr = Newstr(sarg);
			return;
		}
		if (strcmp((char *)word, "LF") == 0) {
		    /*
		     * Left footer
		     */
			Free(&Ftl);
			if (sarg != NULL)
				Ftl = Newstr(sarg);
			return;
		}
		if (strcmp((char *)word, "CF") == 0) {
		    /*
		     * Center footer
		     */
			Free(&Ftc);
			if (sarg != NULL)
				Ftc = Newstr(sarg);
			return;
		}
		if (strcmp((char *)word, "RF") == 0) {
		    /*
		     * Right footer
		     */
			Free(&Ftr);
			if (sarg != NULL)
				Ftr = Newstr(sarg);
			return;
		}
	}
    /*
     * Error on unknown arguments
     */
	Error3(len, (char *)word, (char *)sarg, narg, "unknown request");
}