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diff --git a/Build/source/texk/web2c/luatexdir/dvi/dvigen.w b/Build/source/texk/web2c/luatexdir/dvi/dvigen.w deleted file mode 100644 index d991445a59f..00000000000 --- a/Build/source/texk/web2c/luatexdir/dvi/dvigen.w +++ /dev/null @@ -1,1258 +0,0 @@ -% dvigen.w -% -% Copyright 2009-2013 Taco Hoekwater <taco@@luatex.org> -% -% This file is part of LuaTeX. -% -% LuaTeX 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. -% -% LuaTeX 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 Lesser General Public -% License for more details. -% -% You should have received a copy of the GNU General Public License along -% with LuaTeX; if not, see <http://www.gnu.org/licenses/>. - -\def\MF{MetaFont} -\def\MP{MetaPost} -\def\PASCAL{Pascal} -\def\[#1]{#1} -\pdfoutput=1 -\pdfmapline{cmtex10 < cmtex10.pfb} -\pdfmapfile{pdftex.map} - -\title{: generation of DVI output} - -@ Initial identification of this file, and the needed headers. -@c -#include "ptexlib.h" - -@ Here is the start of the actual C file. -@c -#undef write_dvi - -/* todo: move macros to api */ - -#define mode cur_list.mode_field /* current mode */ - -@ The most important output produced by a run of \TeX\ is the ``device -independent'' (\.{DVI}) file that specifies where characters and rules -are to appear on printed pages. The form of these files was designed by -David R. Fuchs in 1979. Almost any reasonable typesetting device can be -@^Fuchs, David Raymond@> -@:DVI_files}{\.{DVI} files@> -driven by a program that takes \.{DVI} files as input, and dozens of such -\.{DVI}-to-whatever programs have been written. Thus, it is possible to -print the output of \TeX\ on many different kinds of equipment, using \TeX\ -as a device-independent ``front end.'' - -A \.{DVI} file is a stream of 8-bit bytes, which may be regarded as a -series of commands in a machine-like language. The first byte of each command -is the operation code, and this code is followed by zero or more bytes -that provide parameters to the command. The parameters themselves may consist -of several consecutive bytes; for example, the `|set_rule|' command has two -parameters, each of which is four bytes long. Parameters are usually -regarded as nonnegative integers; but four-byte-long parameters, -and shorter parameters that denote distances, can be -either positive or negative. Such parameters are given in two's complement -notation. For example, a two-byte-long distance parameter has a value between -$-2^{15}$ and $2^{15}-1$. As in \.{TFM} files, numbers that occupy -more than one byte position appear in BigEndian order. - -A \.{DVI} file consists of a ``preamble,'' followed by a sequence of one -or more ``pages,'' followed by a ``postamble.'' The preamble is simply a -|pre| command, with its parameters that define the dimensions used in the -file; this must come first. Each ``page'' consists of a |bop| command, -followed by any number of other commands that tell where characters are to -be placed on a physical page, followed by an |eop| command. The pages -appear in the order that \TeX\ generated them. If we ignore |nop| commands -and \\{fnt\_def} commands (which are allowed between any two commands in -the file), each |eop| command is immediately followed by a |bop| command, -or by a |post| command; in the latter case, there are no more pages in the -file, and the remaining bytes form the postamble. Further details about -the postamble will be explained later. - -Some parameters in \.{DVI} commands are ``pointers.'' These are four-byte -quantities that give the location number of some other byte in the file; -the first byte is number~0, then comes number~1, and so on. For example, -one of the parameters of a |bop| command points to the previous |bop|; -this makes it feasible to read the pages in backwards order, in case the -results are being directed to a device that stacks its output face up. -Suppose the preamble of a \.{DVI} file occupies bytes 0 to 99. Now if the -first page occupies bytes 100 to 999, say, and if the second -page occupies bytes 1000 to 1999, then the |bop| that starts in byte 1000 -points to 100 and the |bop| that starts in byte 2000 points to 1000. (The -very first |bop|, i.e., the one starting in byte 100, has a pointer of~$-1$.) - -@ The \.{DVI} format is intended to be both compact and easily interpreted -by a machine. Compactness is achieved by making most of the information -implicit instead of explicit. When a \.{DVI}-reading program reads the -commands for a page, it keeps track of several quantities: (a)~The current -font |f| is an integer; this value is changed only -by \\{fnt} and \\{fnt\_num} commands. (b)~The current position on the page -is given by two numbers called the horizontal and vertical coordinates, -|h| and |v|. Both coordinates are zero at the upper left corner of the page; -moving to the right corresponds to increasing the horizontal coordinate, and -moving down corresponds to increasing the vertical coordinate. Thus, the -coordinates are essentially Cartesian, except that vertical directions are -flipped; the Cartesian version of |(h,v)| would be |(h,-v)|. (c)~The -current spacing amounts are given by four numbers |w|, |x|, |y|, and |z|, -where |w| and~|x| are used for horizontal spacing and where |y| and~|z| -are used for vertical spacing. (d)~There is a stack containing -|(h,v,w,x,y,z)| values; the \.{DVI} commands |push| and |pop| are used to -change the current level of operation. Note that the current font~|f| is -not pushed and popped; the stack contains only information about -positioning. - -The values of |h|, |v|, |w|, |x|, |y|, and |z| are signed integers having up -to 32 bits, including the sign. Since they represent physical distances, -there is a small unit of measurement such that increasing |h| by~1 means -moving a certain tiny distance to the right. The actual unit of -measurement is variable, as explained below; \TeX\ sets things up so that -its \.{DVI} output is in sp units, i.e., scaled points, in agreement with -all the |scaled| dimensions in \TeX's data structures. - -@ Here is a list of all the commands that may appear in a \.{DVI} file. Each -command is specified by its symbolic name (e.g., |bop|), its opcode byte -(e.g., 139), and its parameters (if any). The parameters are followed -by a bracketed number telling how many bytes they occupy; for example, -`|p[4]|' means that parameter |p| is four bytes long. - -\yskip\hang|set_char_0| 0. Typeset character number~0 from font~|f| -such that the reference point of the character is at |(h,v)|. Then -increase |h| by the width of that character. Note that a character may -have zero or negative width, so one cannot be sure that |h| will advance -after this command; but |h| usually does increase. - -\yskip\hang\\{set\_char\_1} through \\{set\_char\_127} (opcodes 1 to 127). -Do the operations of |set_char_0|; but use the character whose number -matches the opcode, instead of character~0. - -\yskip\hang|set1| 128 |c[1]|. Same as |set_char_0|, except that character -number~|c| is typeset. \TeX82 uses this command for characters in the -range |128<=c<256|. - -\yskip\hang|@!set2| 129 |c[2]|. Same as |set1|, except that |c|~is two -bytes long, so it is in the range |0<=c<65536|. \TeX82 never uses this -command, but it should come in handy for extensions of \TeX\ that deal -with oriental languages. -@^oriental characters@>@^Chinese characters@>@^Japanese characters@> - -\yskip\hang|@!set3| 130 |c[3]|. Same as |set1|, except that |c|~is three -bytes long, so it can be as large as $2^{24}-1$. Not even the Chinese -language has this many characters, but this command might prove useful -in some yet unforeseen extension. - -\yskip\hang|@!set4| 131 |c[4]|. Same as |set1|, except that |c|~is four -bytes long. Imagine that. - -\yskip\hang|set_rule| 132 |a[4]| |b[4]|. Typeset a solid black rectangle -of height~|a| and width~|b|, with its bottom left corner at |(h,v)|. Then -set |h:=h+b|. If either |a<=0| or |b<=0|, nothing should be typeset. Note -that if |b<0|, the value of |h| will decrease even though nothing else happens. -See below for details about how to typeset rules so that consistency with -\MF\ is guaranteed. - -\yskip\hang|@!put1| 133 |c[1]|. Typeset character number~|c| from font~|f| -such that the reference point of the character is at |(h,v)|. (The `put' -commands are exactly like the `set' commands, except that they simply put out a -character or a rule without moving the reference point afterwards.) - -\yskip\hang|@!put2| 134 |c[2]|. Same as |set2|, except that |h| is not changed. - -\yskip\hang|@!put3| 135 |c[3]|. Same as |set3|, except that |h| is not changed. - -\yskip\hang|@!put4| 136 |c[4]|. Same as |set4|, except that |h| is not changed. - -\yskip\hang|put_rule| 137 |a[4]| |b[4]|. Same as |set_rule|, except that -|h| is not changed. - -\yskip\hang|nop| 138. No operation, do nothing. Any number of |nop|'s -may occur between \.{DVI} commands, but a |nop| cannot be inserted between -a command and its parameters or between two parameters. - -\yskip\hang|bop| 139 $c_0[4]$ $c_1[4]$ $\ldots$ $c_9[4]$ $p[4]$. Beginning -of a page: Set |(h,v,w,x,y,z):=(0,0,0,0,0,0)| and set the stack empty. Set -the current font |f| to an undefined value. The ten $c_i$ parameters hold -the values of \.{\\count0} $\ldots$ \.{\\count9} in \TeX\ at the time -\.{\\shipout} was invoked for this page; they can be used to identify -pages, if a user wants to print only part of a \.{DVI} file. The parameter -|p| points to the previous |bop| in the file; the first -|bop| has $p=-1$. - -\yskip\hang|eop| 140. End of page: Print what you have read since the -previous |bop|. At this point the stack should be empty. (The \.{DVI}-reading -programs that drive most output devices will have kept a buffer of the -material that appears on the page that has just ended. This material is -largely, but not entirely, in order by |v| coordinate and (for fixed |v|) by -|h|~coordinate; so it usually needs to be sorted into some order that is -appropriate for the device in question.) - -\yskip\hang|push| 141. Push the current values of |(h,v,w,x,y,z)| onto the -top of the stack; do not change any of these values. Note that |f| is -not pushed. - -\yskip\hang|pop| 142. Pop the top six values off of the stack and assign -them respectively to |(h,v,w,x,y,z)|. The number of pops should never -exceed the number of pushes, since it would be highly embarrassing if the -stack were empty at the time of a |pop| command. - -\yskip\hang|right1| 143 |b[1]|. Set |h:=h+b|, i.e., move right |b| units. -The parameter is a signed number in two's complement notation, |-128<=b<128|; -if |b<0|, the reference point moves left. - -\yskip\hang|right2| 144 |b[2]|. Same as |right1|, except that |b| is a -two-byte quantity in the range |-32768<=b<32768|. - -\yskip\hang|right3| 145 |b[3]|. Same as |right1|, except that |b| is a -three-byte quantity in the range |@t$-2^{23}$@><=b<@t$2^{23}$@>|. - -\yskip\hang|right4| 146 |b[4]|. Same as |right1|, except that |b| is a -four-byte quantity in the range |@t$-2^{31}$@><=b<@t$2^{31}$@>|. - -\yskip\hang|w0| 147. Set |h:=h+w|; i.e., move right |w| units. With luck, -this parameterless command will usually suffice, because the same kind of motion -will occur several times in succession; the following commands explain how -|w| gets particular values. - -\yskip\hang|w1| 148 |b[1]|. Set |w:=b| and |h:=h+b|. The value of |b| is a -signed quantity in two's complement notation, |-128<=b<128|. This command -changes the current |w|~spacing and moves right by |b|. - -\yskip\hang|@!w2| 149 |b[2]|. Same as |w1|, but |b| is two bytes long, -|-32768<=b<32768|. - -\yskip\hang|@!w3| 150 |b[3]|. Same as |w1|, but |b| is three bytes long, -|@t$-2^{23}$@><=b<@t$2^{23}$@>|. - -\yskip\hang|@!w4| 151 |b[4]|. Same as |w1|, but |b| is four bytes long, -|@t$-2^{31}$@><=b<@t$2^{31}$@>|. - -\yskip\hang|x0| 152. Set |h:=h+x|; i.e., move right |x| units. The `|x|' -commands are like the `|w|' commands except that they involve |x| instead -of |w|. - -\yskip\hang|x1| 153 |b[1]|. Set |x:=b| and |h:=h+b|. The value of |b| is a -signed quantity in two's complement notation, |-128<=b<128|. This command -changes the current |x|~spacing and moves right by |b|. - -\yskip\hang|@!x2| 154 |b[2]|. Same as |x1|, but |b| is two bytes long, -|-32768<=b<32768|. - -\yskip\hang|@!x3| 155 |b[3]|. Same as |x1|, but |b| is three bytes long, -|@t$-2^{23}$@><=b<@t$2^{23}$@>|. - -\yskip\hang|@!x4| 156 |b[4]|. Same as |x1|, but |b| is four bytes long, -|@t$-2^{31}$@><=b<@t$2^{31}$@>|. - -\yskip\hang|down1| 157 |a[1]|. Set |v:=v+a|, i.e., move down |a| units. -The parameter is a signed number in two's complement notation, |-128<=a<128|; -if |a<0|, the reference point moves up. - -\yskip\hang|@!down2| 158 |a[2]|. Same as |down1|, except that |a| is a -two-byte quantity in the range |-32768<=a<32768|. - -\yskip\hang|@!down3| 159 |a[3]|. Same as |down1|, except that |a| is a -three-byte quantity in the range |@t$-2^{23}$@><=a<@t$2^{23}$@>|. - -\yskip\hang|@!down4| 160 |a[4]|. Same as |down1|, except that |a| is a -four-byte quantity in the range |@t$-2^{31}$@><=a<@t$2^{31}$@>|. - -\yskip\hang|y0| 161. Set |v:=v+y|; i.e., move down |y| units. With luck, -this parameterless command will usually suffice, because the same kind of motion -will occur several times in succession; the following commands explain how -|y| gets particular values. - -\yskip\hang|y1| 162 |a[1]|. Set |y:=a| and |v:=v+a|. The value of |a| is a -signed quantity in two's complement notation, |-128<=a<128|. This command -changes the current |y|~spacing and moves down by |a|. - -\yskip\hang|@!y2| 163 |a[2]|. Same as |y1|, but |a| is two bytes long, -|-32768<=a<32768|. - -\yskip\hang|@!y3| 164 |a[3]|. Same as |y1|, but |a| is three bytes long, -|@t$-2^{23}$@><=a<@t$2^{23}$@>|. - -\yskip\hang|@!y4| 165 |a[4]|. Same as |y1|, but |a| is four bytes long, -|@t$-2^{31}$@><=a<@t$2^{31}$@>|. - -\yskip\hang|z0| 166. Set |v:=v+z|; i.e., move down |z| units. The `|z|' commands -are like the `|y|' commands except that they involve |z| instead of |y|. - -\yskip\hang|z1| 167 |a[1]|. Set |z:=a| and |v:=v+a|. The value of |a| is a -signed quantity in two's complement notation, |-128<=a<128|. This command -changes the current |z|~spacing and moves down by |a|. - -\yskip\hang|@!z2| 168 |a[2]|. Same as |z1|, but |a| is two bytes long, -|-32768<=a<32768|. - -\yskip\hang|@!z3| 169 |a[3]|. Same as |z1|, but |a| is three bytes long, -|@t$-2^{23}$@><=a<@t$2^{23}$@>|. - -\yskip\hang|@!z4| 170 |a[4]|. Same as |z1|, but |a| is four bytes long, -|@t$-2^{31}$@><=a<@t$2^{31}$@>|. - -\yskip\hang|fnt_num_0| 171. Set |f:=0|. Font 0 must previously have been -defined by a \\{fnt\_def} instruction, as explained below. - -\yskip\hang\\{fnt\_num\_1} through \\{fnt\_num\_63} (opcodes 172 to 234). Set -|f:=1|, \dots, \hbox{|f:=63|}, respectively. - -\yskip\hang|fnt1| 235 |k[1]|. Set |f:=k|. \TeX82 uses this command for font -numbers in the range |64<=k<256|. - -\yskip\hang|@!fnt2| 236 |k[2]|. Same as |fnt1|, except that |k|~is two -bytes long, so it is in the range |0<=k<65536|. \TeX82 never generates this -command, but large font numbers may prove useful for specifications of -color or texture, or they may be used for special fonts that have fixed -numbers in some external coding scheme. - -\yskip\hang|@!fnt3| 237 |k[3]|. Same as |fnt1|, except that |k|~is three -bytes long, so it can be as large as $2^{24}-1$. - -\yskip\hang|@!fnt4| 238 |k[4]|. Same as |fnt1|, except that |k|~is four -bytes long; this is for the really big font numbers (and for the negative ones). - -\yskip\hang|xxx1| 239 |k[1]| |x[k]|. This command is undefined in -general; it functions as a $(k+2)$-byte |nop| unless special \.{DVI}-reading -programs are being used. \TeX82 generates |xxx1| when a short enough -\.{\\special} appears, setting |k| to the number of bytes being sent. It -is recommended that |x| be a string having the form of a keyword followed -by possible parameters relevant to that keyword. - -\yskip\hang|@!xxx2| 240 |k[2]| |x[k]|. Like |xxx1|, but |0<=k<65536|. - -\yskip\hang|@!xxx3| 241 |k[3]| |x[k]|. Like |xxx1|, but |0<=k<@t$2^{24}$@>|. - -\yskip\hang|xxx4| 242 |k[4]| |x[k]|. Like |xxx1|, but |k| can be ridiculously -large. \TeX82 uses |xxx4| when sending a string of length 256 or more. - -\yskip\hang|fnt_def1| 243 |k[1]| |c[4]| |s[4]| |d[4]| |a[1]| |l[1]| |n[a+l]|. -Define font |k|, where |0<=k<256|; font definitions will be explained shortly. - -\yskip\hang|@!fnt_def2| 244 |k[2]| |c[4]| |s[4]| |d[4]| |a[1]| |l[1]| |n[a+l]|. -Define font |k|, where |0<=k<65536|. - -\yskip\hang|@!fnt_def3| 245 |k[3]| |c[4]| |s[4]| |d[4]| |a[1]| |l[1]| |n[a+l]|. -Define font |k|, where |0<=k<@t$2^{24}$@>|. - -\yskip\hang|@!fnt_def4| 246 |k[4]| |c[4]| |s[4]| |d[4]| |a[1]| |l[1]| |n[a+l]|. -Define font |k|, where |@t$-2^{31}$@><=k<@t$2^{31}$@>|. - -\yskip\hang|pre| 247 |i[1]| |num[4]| |den[4]| |mag[4]| |k[1]| |x[k]|. -Beginning of the preamble; this must come at the very beginning of the -file. Parameters |i|, |num|, |den|, |mag|, |k|, and |x| are explained below. - -\yskip\hang|post| 248. Beginning of the postamble, see below. - -\yskip\hang|post_post| 249. Ending of the postamble, see below. - -\yskip\noindent Commands 250--255 are undefined at the present time. - -@c -#define set_char_0 0 /* typeset character 0 and move right */ -#define set1 128 /* typeset a character and move right */ -#define set_rule 132 /* typeset a rule and move right */ -#define put1 133 /* typeset a character without moving */ -#define put_rule 137 /* typeset a rule */ -#define nop 138 /* no operation */ -#define bop 139 /* beginning of page */ -#define eop 140 /* ending of page */ -#define push 141 /* save the current positions */ -#define pop 142 /* restore previous positions */ -#define right1 143 /* move right */ -#define right4 146 /* move right, 4 bytes */ -#define w0 147 /* move right by |w| */ -#define w1 148 /* move right and set |w| */ -#define x0 152 /* move right by |x| */ -#define x1 153 /* move right and set |x| */ -#define down1 157 /* move down */ -#define down4 160 /* move down, 4 bytes */ -#define y0 161 /* move down by |y| */ -#define y1 162 /* move down and set |y| */ -#define z0 166 /* move down by |z| */ -#define z1 167 /* move down and set |z| */ -#define fnt_num_0 171 /* set current font to 0 */ -#define fnt1 235 /* set current font */ -#define xxx1 239 /* extension to \.{DVI} primitives */ -#define xxx4 242 /* potentially long extension to \.{DVI} primitives */ -#define fnt_def1 243 /* define the meaning of a font number */ -#define pre 247 /* preamble */ -#define post 248 /* postamble beginning */ -#define post_post 249 /* postamble ending */ - -@ The preamble contains basic information about the file as a whole. As -stated above, there are six parameters: -$$\hbox{|@!i[1]| |@!num[4]| |@!den[4]| |@!mag[4]| |@!k[1]| |@!x[k]|.}$$ -The |i| byte identifies \.{DVI} format; currently this byte is always set -to~2. (The value |i=3| is currently used for an extended format that -allows a mixture of right-to-left and left-to-right typesetting. -Some day we will set |i=4|, when \.{DVI} format makes another -incompatible change---perhaps in the year 2048.) - -The next two parameters, |num| and |den|, are positive integers that define -the units of measurement; they are the numerator and denominator of a -fraction by which all dimensions in the \.{DVI} file could be multiplied -in order to get lengths in units of $10^{-7}$ meters. Since $\rm 7227{pt} = -254{cm}$, and since \TeX\ works with scaled points where there are $2^{16}$ -sp in a point, \TeX\ sets -$|num|/|den|=(254\cdot10^5)/(7227\cdot2^{16})=25400000/473628672$. -@^sp@> - -The |mag| parameter is what \TeX\ calls \.{\\mag}, i.e., 1000 times the -desired magnification. The actual fraction by which dimensions are -multiplied is therefore $|mag|\cdot|num|/1000|den|$. Note that if a \TeX\ -source document does not call for any `\.{true}' dimensions, and if you -change it only by specifying a different \.{\\mag} setting, the \.{DVI} -file that \TeX\ creates will be completely unchanged except for the value -of |mag| in the preamble and postamble. (Fancy \.{DVI}-reading programs allow -users to override the |mag|~setting when a \.{DVI} file is being printed.) - -Finally, |k| and |x| allow the \.{DVI} writer to include a comment, which is not -interpreted further. The length of comment |x| is |k|, where |0<=k<256|. - - -@c -#define id_byte 2 /* identifies the kind of \.{DVI} files described here */ - -@ Font definitions for a given font number |k| contain further parameters -$$\hbox{|c[4]| |s[4]| |d[4]| |a[1]| |l[1]| |n[a+l]|.}$$ -The four-byte value |c| is the check sum that \TeX\ found in the \.{TFM} -file for this font; |c| should match the check sum of the font found by -programs that read this \.{DVI} file. -@^check sum@> - -Parameter |s| contains a fixed-point scale factor that is applied to -the character widths in font |k|; font dimensions in \.{TFM} files and -other font files are relative to this quantity, which is called the -``at size'' elsewhere in this documentation. The value of |s| is -always positive and less than $2^{27}$. It is given in the same units -as the other \.{DVI} dimensions, i.e., in sp when \TeX82 has made the -file. Parameter |d| is similar to |s|; it is the ``design size,'' and -(like~|s|) it is given in \.{DVI} units. Thus, font |k| is to be used -at $|mag|\cdot s/1000d$ times its normal size. - -The remaining part of a font definition gives the external name of the font, -which is an ASCII string of length |a+l|. The number |a| is the length -of the ``area'' or directory, and |l| is the length of the font name itself; -the standard local system font area is supposed to be used when |a=0|. -The |n| field contains the area in its first |a| bytes. - -Font definitions must appear before the first use of a particular font number. -Once font |k| is defined, it must not be defined again; however, we -shall see below that font definitions appear in the postamble as well as -in the pages, so in this sense each font number is defined exactly twice, -if at all. Like |nop| commands, font definitions can -appear before the first |bop|, or between an |eop| and a |bop|. - -@ Sometimes it is desirable to make horizontal or vertical rules line up -precisely with certain features in characters of a font. It is possible to -guarantee the correct matching between \.{DVI} output and the characters -generated by \MF\ by adhering to the following principles: (1)~The \MF\ -characters should be positioned so that a bottom edge or left edge that is -supposed to line up with the bottom or left edge of a rule appears at the -reference point, i.e., in row~0 and column~0 of the \MF\ raster. This -ensures that the position of the rule will not be rounded differently when -the pixel size is not a perfect multiple of the units of measurement in -the \.{DVI} file. (2)~A typeset rule of height $a>0$ and width $b>0$ -should be equivalent to a \MF-generated character having black pixels in -precisely those raster positions whose \MF\ coordinates satisfy -|0<=x<@t$\alpha$@>b| and |0<=y<@t$\alpha$@>a|, where $\alpha$ is the number -of pixels per \.{DVI} unit. -@:METAFONT}{\MF@> -@^alignment of rules with characters@> -@^rules aligning with characters@> - -@ The last page in a \.{DVI} file is followed by `|post|'; this command -introduces the postamble, which summarizes important facts that \TeX\ has -accumulated about the file, making it possible to print subsets of the data -with reasonable efficiency. The postamble has the form -$$\vbox{\halign{\hbox{#\hfil}\cr - |post| |p[4]| |num[4]| |den[4]| |mag[4]| |l[4]| |u[4]| |s[2]| |t[2]|\cr - $\langle\,$font definitions$\,\rangle$\cr - |post_post| |q[4]| |i[1]| 223's$[{\G}4]$\cr}}$$ -Here |p| is a pointer to the final |bop| in the file. The next three -parameters, |num|, |den|, and |mag|, are duplicates of the quantities that -appeared in the preamble. - -Parameters |l| and |u| give respectively the height-plus-depth of the tallest -page and the width of the widest page, in the same units as other dimensions -of the file. These numbers might be used by a \.{DVI}-reading program to -position individual ``pages'' on large sheets of film or paper; however, -the standard convention for output on normal size paper is to position each -page so that the upper left-hand corner is exactly one inch from the left -and the top. Experience has shown that it is unwise to design \.{DVI}-to-printer -software that attempts cleverly to center the output; a fixed position of -the upper left corner is easiest for users to understand and to work with. -Therefore |l| and~|u| are often ignored. - -Parameter |s| is the maximum stack depth (i.e., the largest excess of -|push| commands over |pop| commands) needed to process this file. Then -comes |t|, the total number of pages (|bop| commands) present. - -The postamble continues with font definitions, which are any number of -\\{fnt\_def} commands as described above, possibly interspersed with |nop| -commands. Each font number that is used in the \.{DVI} file must be defined -exactly twice: Once before it is first selected by a \\{fnt} command, and once -in the postamble. - -@ The last part of the postamble, following the |post_post| byte that -signifies the end of the font definitions, contains |q|, a pointer to the -|post| command that started the postamble. An identification byte, |i|, -comes next; this currently equals~2, as in the preamble. - -The |i| byte is followed by four or more bytes that are all equal to -the decimal number 223 (i.e., '337 in octal). \TeX\ puts out four to seven of -these trailing bytes, until the total length of the file is a multiple of -four bytes, since this works out best on machines that pack four bytes per -word; but any number of 223's is allowed, as long as there are at least four -of them. In effect, 223 is a sort of signature that is added at the very end. -@^Fuchs, David Raymond@> - -This curious way to finish off a \.{DVI} file makes it feasible for -\.{DVI}-reading programs to find the postamble first, on most computers, -even though \TeX\ wants to write the postamble last. Most operating -systems permit random access to individual words or bytes of a file, so -the \.{DVI} reader can start at the end and skip backwards over the 223's -until finding the identification byte. Then it can back up four bytes, read -|q|, and move to byte |q| of the file. This byte should, of course, -contain the value 248 (|post|); now the postamble can be read, so the -\.{DVI} reader can discover all the information needed for typesetting the -pages. Note that it is also possible to skip through the \.{DVI} file at -reasonably high speed to locate a particular page, if that proves -desirable. This saves a lot of time, since \.{DVI} files used in production -jobs tend to be large. - -Unfortunately, however, standard \PASCAL\ does not include the ability to -@^system dependencies@> -access a random position in a file, or even to determine the length of a file. -Almost all systems nowadays provide the necessary capabilities, so \.{DVI} -format has been designed to work most efficiently with modern operating systems. -But if \.{DVI} files have to be processed under the restrictions of standard -\PASCAL, one can simply read them from front to back, since the necessary -header information is present in the preamble and in the font definitions. -(The |l| and |u| and |s| and |t| parameters, which appear only in the -postamble, are ``frills'' that are handy but not absolutely necessary.) - - -@* \[32] Shipping pages out. -After considering \TeX's eyes and stomach, we come now to the bowels. -@^bowels@> - -The |ship_out| procedure is given a pointer to a box; its mission is -to describe that box in \.{DVI} form, outputting a ``page'' to |dvi_file|. -The \.{DVI} coordinates $(h,v)=(0,0)$ should correspond to the upper left -corner of the box being shipped. - -Since boxes can be inside of boxes inside of boxes, the main work of -|ship_out| is done by two mutually recursive routines, |hlist_out| -and |vlist_out|, which traverse the hlists and vlists inside of horizontal -and vertical boxes. - -As individual pages are being processed, we need to accumulate -information about the entire set of pages, since such statistics must be -reported in the postamble. The global variables |total_pages|, |max_v|, -|max_h|, |max_push|, and |last_bop| are used to record this information. - -The variable |doing_leaders| is |true| while leaders are being output. -The variable |dead_cycles| contains the number of times an output routine -has been initiated since the last |ship_out|. - -A few additional global variables are also defined here for use in -|vlist_out| and |hlist_out|. They could have been local variables, but -that would waste stack space when boxes are deeply nested, since the -values of these variables are not needed during recursive calls. -@^recursion@> - -@c -int total_pages = 0; /* the number of pages that have been shipped out */ -scaled max_v = 0; /* maximum height-plus-depth of pages shipped so far */ -scaled max_h = 0; /* maximum width of pages shipped so far */ -int max_push = 0; /* deepest nesting of |push| commands encountered so far */ -int last_bop = -1; /* location of previous |bop| in the \.{DVI} output */ -int dead_cycles = 0; /* recent outputs that didn't ship anything out */ -boolean doing_leaders = false; /* are we inside a leader box? */ -int oval, ocmd; /* used by |out_cmd| for generating |set|, |fnt| and |fnt_def| commands */ -pointer g; /* current glue specification */ -int lq, lr; /* quantities used in calculations for leaders */ -int cur_s = -1; /* current depth of output box nesting, initially $-1$ */ - -@ The \.{DVI} bytes are output to a buffer instead of being written directly -to the output file. This makes it possible to reduce the overhead of -subroutine calls, thereby measurably speeding up the computation, since -output of \.{DVI} bytes is part of \TeX's inner loop. And it has another -advantage as well, since we can change instructions in the buffer in order to -make the output more compact. For example, a `|down2|' command can be -changed to a `|y2|', thereby making a subsequent `|y0|' command possible, -saving two bytes. - -The output buffer is divided into two parts of equal size; the bytes found -in |dvi_buf[0..half_buf-1]| constitute the first half, and those in -|dvi_buf[half_buf..dvi_buf_size-1]| constitute the second. The global -variable |dvi_ptr| points to the position that will receive the next -output byte. When |dvi_ptr| reaches |dvi_limit|, which is always equal -to one of the two values |half_buf| or |dvi_buf_size|, the half buffer that -is about to be invaded next is sent to the output and |dvi_limit| is -changed to its other value. Thus, there is always at least a half buffer's -worth of information present, except at the very beginning of the job. - -Bytes of the \.{DVI} file are numbered sequentially starting with 0; -the next byte to be generated will be number |dvi_offset+dvi_ptr|. -A byte is present in the buffer only if its number is |>=dvi_gone|. - -Some systems may find it more efficient to make |dvi_buf| a |packed| -array, since output of four bytes at once may be facilitated. -@^system dependencies@> - - -@ Initially the buffer is all in one piece; we will output half of it only -after it first fills up. - -@c -int dvi_buf_size = 800; /* size of the output buffer; must be a multiple of 8 */ -eight_bits *dvi_buf; /* buffer for \.{DVI} output */ -dvi_index half_buf = 0; /* half of |dvi_buf_size| */ -dvi_index dvi_limit = 0; /* end of the current half buffer */ -dvi_index dvi_ptr = 0; /* the next available buffer address */ -int dvi_offset = 0; /* |dvi_buf_size| times the number of times the output buffer has been fully emptied */ -int dvi_gone = 0; /* the number of bytes already output to |dvi_file| */ - -@ The actual output of |dvi_buf[a..b]| to |dvi_file| is performed by calling -|write_dvi(a,b)|. For best results, this procedure should be optimized to -run as fast as possible on each particular system, since it is part of -\TeX's inner loop. It is safe to assume that |a| and |b+1| will both be -multiples of 4 when |write_dvi(a,b)| is called; therefore it is possible on -many machines to use efficient methods to pack four bytes per word and to -output an array of words with one system call. -@^system dependencies@> -@^inner loop@> -@^defecation@> - -@c -static void write_dvi(dvi_index a, dvi_index b) -{ - dvi_index k; - for (k = a; k <= b; k++) - fputc(dvi_buf[k], static_pdf->file); -} - -/* outputs half of the buffer */ -void dvi_swap(void) -{ - if (dvi_limit == dvi_buf_size) { - write_dvi(0, half_buf - 1); - dvi_limit = half_buf; - dvi_offset = dvi_offset + dvi_buf_size; - dvi_ptr = 0; - } else { - write_dvi(half_buf, dvi_buf_size - 1); - dvi_limit = dvi_buf_size; - } - dvi_gone = dvi_gone + half_buf; -} - -@ The |dvi_four| procedure outputs four bytes in two's complement notation, -without risking arithmetic overflow. - -@c -void dvi_four(int x) -{ - if (x >= 0) { - dvi_out(x / 0100000000); - } else { - x = x + 010000000000; - x = x + 010000000000; - dvi_out((x / 0100000000) + 128); - } - x = x % 0100000000; - dvi_out(x / 0200000); - x = x % 0200000; - dvi_out(x / 0400); - dvi_out(x % 0400); -} - -@ -A mild optimization of the output is performed by the |dvi_pop| -routine, which issues a |pop| unless it is possible to cancel a -`|push| |pop|' pair. The parameter to |dvi_pop| is the byte address -following the old |push| that matches the new |pop|. - - -@c -void dvi_push(void) -{ - dvi_out(push); -} - -void dvi_pop(int l) -{ - if ((l == dvi_offset + dvi_ptr) && (dvi_ptr > 0)) - decr(dvi_ptr); - else - dvi_out(pop); -} - -@ Here's a procedure that outputs a font definition. $\Omega$ allows -more than 256 different fonts per job, so the right font definition -command must be selected. - -@c -void out_cmd(void) -{ - if ((oval < 0x100) && (oval >= 0)) { - if ((ocmd != set1) || (oval > 127)) { - if ((ocmd == fnt1) && (oval < 64)) - oval += fnt_num_0; - else - dvi_out(ocmd); - } - } else { - if ((oval < 0x10000) && (oval >= 0)) { - dvi_out(ocmd + 1); - } else { - if ((oval < 0x1000000) && (oval >= 0)) { - dvi_out(ocmd + 2); - } else { - dvi_out(ocmd + 3); - if (oval >= 0) { - dvi_out(oval / 0x1000000); - } else { - oval += 0x40000000; - oval += 0x40000000; - dvi_out((oval / 0x1000000) + 128); - oval = oval % 0x1000000; - } - dvi_out(oval / 0x10000); - oval = oval % 0x10000; - } - dvi_out(oval / 0x10000); - oval = oval % 0x10000; - } - dvi_out(oval / 0x100); - oval = oval % 0x100; - } - dvi_out(oval); -} - -void dvi_font_def(internal_font_number f) -{ - char *fa; - oval = f - 1; - ocmd = fnt_def1; - out_cmd(); - dvi_out(font_check_0(f)); - dvi_out(font_check_1(f)); - dvi_out(font_check_2(f)); - dvi_out(font_check_3(f)); - dvi_four(font_size(f)); - dvi_four(font_dsize(f)); - dvi_out(0); /* |font_area(f)| is unused */ - dvi_out(strlen(font_name(f))); - /* Output the font name whose internal number is |f| */ - fa = font_name(f); - while (*fa != '\0') { - dvi_out(*fa++); - } -} - -@ Versions of \TeX\ intended for small computers might well choose to omit -the ideas in the next few parts of this program, since it is not really -necessary to optimize the \.{DVI} code by making use of the |w0|, |x0|, -|y0|, and |z0| commands. Furthermore, the algorithm that we are about to -describe does not pretend to give an optimum reduction in the length -of the \.{DVI} code; after all, speed is more important than compactness. -But the method is surprisingly effective, and it takes comparatively little -time. - -We can best understand the basic idea by first considering a simpler problem -that has the same essential characteristics. Given a sequence of digits, -say $3\,1\,4\,1\,5\,9\,2\,6\,5\,3\,5\,8\,9$, we want to assign subscripts -$d$, $y$, or $z$ to each digit so as to maximize the number of ``$y$-hits'' -and ``$z$-hits''; a $y$-hit is an instance of two appearances of the same -digit with the subscript $y$, where no $y$'s intervene between the two -appearances, and a $z$-hit is defined similarly. For example, the sequence -above could be decorated with subscripts as follows: -$$3_z\,1_y\,4_d\,1_y\,5_y\,9_d\,2_d\,6_d\,5_y\,3_z\,5_y\,8_d\,9_d.$$ -There are three $y$-hits ($1_y\ldots1_y$ and $5_y\ldots5_y\ldots5_y$) and -one $z$-hit ($3_z\ldots3_z$); there are no $d$-hits, since the two appearances -of $9_d$ have $d$'s between them, but we don't count $d$-hits so it doesn't -matter how many there are. These subscripts are analogous to the \.{DVI} -commands called \\{down}, $y$, and $z$, and the digits are analogous to -different amounts of vertical motion; a $y$-hit or $z$-hit corresponds to -the opportunity to use the one-byte commands |y0| or |z0| in a \.{DVI} file. - -\TeX's method of assigning subscripts works like this: Append a new digit, -say $\delta$, to the right of the sequence. Now look back through the -sequence until one of the following things happens: (a)~You see -$\delta_y$ or $\delta_z$, and this was the first time you encountered a -$y$ or $z$ subscript, respectively. Then assign $y$ or $z$ to the new -$\delta$; you have scored a hit. (b)~You see $\delta_d$, and no $y$ -subscripts have been encountered so far during this search. Then change -the previous $\delta_d$ to $\delta_y$ (this corresponds to changing a -command in the output buffer), and assign $y$ to the new $\delta$; it's -another hit. (c)~You see $\delta_d$, and a $y$ subscript has been seen -but not a $z$. Change the previous $\delta_d$ to $\delta_z$ and assign -$z$ to the new $\delta$. (d)~You encounter both $y$ and $z$ subscripts -before encountering a suitable $\delta$, or you scan all the way to the -front of the sequence. Assign $d$ to the new $\delta$; this assignment may -be changed later. - -The subscripts $3_z\,1_y\,4_d\ldots\,$ in the example above were, in fact, -produced by this procedure, as the reader can verify. (Go ahead and try it.) - -@ In order to implement such an idea, \TeX\ maintains a stack of pointers -to the \\{down}, $y$, and $z$ commands that have been generated for the -current page. And there is a similar stack for \\{right}, |w|, and |x| -commands. These stacks are called the down stack and right stack, and their -top elements are maintained in the variables |down_ptr| and |right_ptr|. - -Each entry in these stacks contains four fields: The |width| field is -the amount of motion down or to the right; the |location| field is the -byte number of the \.{DVI} command in question (including the appropriate -|dvi_offset|); the |vlink| field points to the next item below this one -on the stack; and the |vinfo| field encodes the options for possible change -in the \.{DVI} command. - -@c -#define location(A) varmem[(A)+1].cint /* \.{DVI} byte number for a movement command */ - -halfword down_ptr = null, right_ptr = null; /* heads of the down and right stacks */ - -@ Here is a subroutine that produces a \.{DVI} command for some specified -downward or rightward motion. It has two parameters: |w| is the amount -of motion, and |o| is either |down1| or |right1|. We use the fact that -the command codes have convenient arithmetic properties: |y1-down1=w1-right1| -and |z1-down1=x1-right1|. - -@c -void movement(scaled w, eight_bits o) -{ - small_number mstate; /* have we seen a |y| or |z|? */ - halfword p, q; /* current and top nodes on the stack */ - int k; /* index into |dvi_buf|, modulo |dvi_buf_size| */ - if (false) { /* TODO: HUH? */ - q = new_node(movement_node, 0); /* new node for the top of the stack */ - width(q) = w; - location(q) = dvi_offset + dvi_ptr; - if (o == down1) { - vlink(q) = down_ptr; - down_ptr = q; - } else { - vlink(q) = right_ptr; - right_ptr = q; - } - /* Look at the other stack entries until deciding what sort of \.{DVI} command - to generate; |goto found| if node |p| is a ``hit'' */ - p = vlink(q); - mstate = none_seen; - while (p != null) { - if (width(p) == w) { - /* Consider a node with matching width;|goto found| if it's a hit */ - /* We might find a valid hit in a |y| or |z| byte that is already gone - from the buffer. But we can't change bytes that are gone forever; ``the - moving finger writes, $\ldots\,\,$.'' */ - - switch (mstate + vinfo(p)) { - case none_seen + yz_OK: - case none_seen + y_OK: - case z_seen + yz_OK: - case z_seen + y_OK: - if (location(p) < dvi_gone) { - goto NOT_FOUND; - } else { - /* Change buffered instruction to |y| or |w| and |goto found| */ - k = location(p) - dvi_offset; - if (k < 0) - k = k + dvi_buf_size; - dvi_buf[k] = (eight_bits) (dvi_buf[k] + y1 - down1); - vinfo(p) = y_here; - goto FOUND; - } - break; - case none_seen + z_OK: - case y_seen + yz_OK: - case y_seen + z_OK: - if (location(p) < dvi_gone) { - goto NOT_FOUND; - } else { - /* Change buffered instruction to |z| or |x| and |goto found| */ - k = location(p) - dvi_offset; - if (k < 0) - k = k + dvi_buf_size; - dvi_buf[k] = (eight_bits) (dvi_buf[k] + z1 - down1); - vinfo(p) = z_here; - goto FOUND; - } - break; - case none_seen + y_here: - case none_seen + z_here: - case y_seen + z_here: - case z_seen + y_here: - goto FOUND; - break; - default: - break; - } - } else { - switch (mstate + vinfo(p)) { - case none_seen + y_here: - mstate = y_seen; - break; - case none_seen + z_here: - mstate = z_seen; - break; - case y_seen + z_here: - case z_seen + y_here: - goto NOT_FOUND; - break; - default: - break; - } - } - p = vlink(p); - } - } - NOT_FOUND: - /* Generate a |down| or |right| command for |w| and |return| */ - if (abs(w) >= 040000000) { - dvi_out(o + 3); /* |down4| or |right4| */ - dvi_four(w); - return; - } - if (abs(w) >= 0100000) { - dvi_out(o + 2); /* |down3| or |right3| */ - if (w < 0) - w = w + 0100000000; - dvi_out(w / 0200000); - w = w % 0200000; - goto TWO; - } - if (abs(w) >= 0200) { - dvi_out(o + 1); /* |down2| or |right2| */ - if (w < 0) - w = w + 0200000; - goto TWO; - } - dvi_out(o); /* |down1| or |right1| */ - if (w < 0) - w = w + 0400; - goto ONE; - TWO: - dvi_out(w / 0400); - ONE: - dvi_out(w % 0400); - return; - FOUND: - /* Generate a |y0| or |z0| command in order to reuse a previous appearance of~|w| */ - /* The program below removes movement nodes that are introduced after a |push|, - before it outputs the corresponding |pop|. */ - /* - When the |movement| procedure gets to the label |found|, the value of - |vinfo(p)| will be either |y_here| or |z_here|. If it is, say, |y_here|, - the procedure generates a |y0| command (or a |w0| command), and marks - all |vinfo| fields between |q| and |p| so that |y| is not OK in that range. - */ - vinfo(q) = vinfo(p); - if (vinfo(q) == y_here) { - dvi_out(o + y0 - down1); /* |y0| or |w0| */ - while (vlink(q) != p) { - q = vlink(q); - switch (vinfo(q)) { - case yz_OK: - vinfo(q) = z_OK; - break; - case y_OK: - vinfo(q) = d_fixed; - break; - default: - break; - } - } - } else { - dvi_out(o + z0 - down1); /* |z0| or |x0| */ - while (vlink(q) != p) { - q = vlink(q); - switch (vinfo(q)) { - case yz_OK: - vinfo(q) = y_OK; - break; - case z_OK: - vinfo(q) = d_fixed; - break; - default: - break; - } - } - } -} - -@ In case you are wondering when all the movement nodes are removed from -\TeX's memory, the answer is that they are recycled just before -|hlist_out| and |vlist_out| finish outputting a box. This restores the -down and right stacks to the state they were in before the box was output, -except that some |vinfo|'s may have become more restrictive. - - -@c -/* delete movement nodes with |location>=l| */ -void prune_movements(int l) -{ - pointer p; /* node being deleted */ - while (down_ptr != null) { - if (location(down_ptr) < l) - break; - p = down_ptr; - down_ptr = vlink(p); - flush_node(p); - } - while (right_ptr != null) { - if (location(right_ptr) < l) - return; - p = right_ptr; - right_ptr = vlink(p); - flush_node(p); - } -} - -scaledpos dvi; /* a \.{DVI} position in page coordinates, in sync with DVI file */ - -@ When |hlist_out| is called, its duty is to output the box represented -by the |hlist_node| pointed to by |temp_ptr|. The reference point of that -box has coordinates |(cur.h,cur.v)|. - -Similarly, when |vlist_out| is called, its duty is to output the box represented -by the |vlist_node| pointed to by |temp_ptr|. The reference point of that -box has coordinates |(cur.h,cur.v)|. -@^recursion@> - -@ The recursive procedures |hlist_out| and |vlist_out| each have a local variable -|save_dvi| to hold the value of |dvi| just before -entering a new level of recursion. In effect, the value of |save_dvi| -on \TeX's run-time stack corresponds to the values of |h| and |v| -that a \.{DVI}-reading program will push onto its coordinate stack. - -@c -void dvi_place_rule(PDF pdf, halfword q, scaledpos size) -{ - synch_dvi_with_pos(pdf->posstruct->pos); - if ((subtype(q) >= box_rule) && (subtype(q) <= user_rule)) { - /* place nothing, only take space */ - if (textdir_is_L(pdf->posstruct->dir)) - dvi.h += size.h; - } else { - /* normal_rule or >= 100 being a leader rule */ - if (textdir_is_L(pdf->posstruct->dir)) { - dvi_out(set_rule); /* movement optimization for |dir_*L*| */ - dvi.h += size.h; - } else - dvi_out(put_rule); - } - dvi_four(size.v); - dvi_four(size.h); -} - -void dvi_place_glyph(PDF pdf, internal_font_number f, int c, int ex) -{ - /* TODO: do something on ex, select font (if possible) */ - scaled_whd ci; - synch_dvi_with_pos(pdf->posstruct->pos); - if (f != pdf->f_cur) { - /* Change font |f_cur| to |f| */ - if (!font_used(f)) { - dvi_font_def(f); - set_font_used(f, true); - } - oval = f - 1; - ocmd = fnt1; - out_cmd(); - pdf->f_cur = f; - } - if (textdir_is_L(pdf->posstruct->dir)) { - ci = get_charinfo_whd(f, c); - dvi_set(c, ci.wd); /* movement optimization for |dir_*L*| */ - } else - dvi_put(c); -} - -void dvi_special(PDF pdf, halfword p) -{ - int old_setting; /* holds print |selector| */ - unsigned k; /* index into |cur_string| */ - synch_dvi_with_pos(pdf->posstruct->pos); - old_setting = selector; - selector = new_string; - show_token_list(token_link(write_tokens(p)), null, -1); - selector = old_setting; - if (cur_length < 256) { - dvi_out(xxx1); - dvi_out(cur_length); - } else { - dvi_out(xxx4); - dvi_four((int) cur_length); - } - for (k = 0; k < cur_length; k++) - dvi_out(cur_string[k]); - cur_length = 0; /* erase the string */ -} - -@ Here's an example of how these conventions are used. Whenever it is time to -ship out a box of stuff, we shall use the macro |ensure_dvi_open|. - -@c -void ensure_dvi_header_written(PDF pdf) -{ - unsigned l; - unsigned s; /* index into |str_pool| */ - int old_setting; /* saved |selector| setting */ - assert(output_mode_used == OMODE_DVI); - assert(pdf->o_state == ST_FILE_OPEN); - - if (half_buf == 0) { - half_buf = dvi_buf_size / 2; - dvi_limit = dvi_buf_size; - } - - dvi_out(pre); - dvi_out(id_byte); /* output the preamble */ - dvi_four(25400000); - dvi_four(473628672); /* conversion ratio for sp */ - prepare_mag(); - dvi_four(mag_par); /* magnification factor is frozen */ - if (output_comment) { - l = (unsigned) strlen(output_comment); - dvi_out(l); - for (s = 0; s < l; s++) - dvi_out(output_comment[s]); - } else { /* the default code is unchanged */ - old_setting = selector; - selector = new_string; - tprint(" LuaTeX output "); - print_int(year_par); - print_char('.'); - print_two(month_par); - print_char('.'); - print_two(day_par); - print_char(':'); - print_two(time_par / 60); - print_two(time_par % 60); - selector = old_setting; - dvi_out(cur_length); - for (s = 0; s < cur_length; s++) - dvi_out(cur_string[s]); - cur_length = 0; - } -} - -void dvi_begin_page(PDF pdf) -{ - int k; - int page_loc; /* location of the current |bop| */ - ensure_output_state(pdf, ST_HEADER_WRITTEN); - /* Initialize variables as |ship_out| begins */ - page_loc = dvi_offset + dvi_ptr; - dvi_out(bop); - for (k = 0; k <= 9; k++) - dvi_four(count(k)); - dvi_four(last_bop); - last_bop = page_loc; -} - -void dvi_end_page(PDF pdf) -{ - (void) pdf; - dvi_out(eop); -} - -@ At the end of the program, we must finish things off by writing the -post\-amble. If |total_pages=0|, the \.{DVI} file was never opened. -If |total_pages>=65536|, the \.{DVI} file will lie. And if -|max_push>=65536|, the user deserves whatever chaos might ensue. - -@c -void finish_dvi_file(PDF pdf, int version, int revision) -{ - int k; - int callback_id = callback_defined(stop_run_callback); - (void) version; - (void) revision; - while (cur_s > -1) { - if (cur_s > 0) { - dvi_out(pop); - } else { - dvi_out(eop); - incr(total_pages); - } - decr(cur_s); - } - if (total_pages == 0) { - if (callback_id == 0) { - tprint_nl("No pages of output."); - print_ln(); - } else if (callback_id > 0) { - run_callback(callback_id, "->"); - } - } else { - dvi_out(post); /* beginning of the postamble */ - dvi_four(last_bop); - last_bop = dvi_offset + dvi_ptr - 5; /* |post| location */ - dvi_four(25400000); - dvi_four(473628672); /* conversion ratio for sp */ - prepare_mag(); - dvi_four(mag_par); /* magnification factor */ - dvi_four(max_v); - dvi_four(max_h); - dvi_out(max_push / 256); - dvi_out(max_push % 256); - dvi_out((total_pages / 256) % 256); - dvi_out(total_pages % 256); - /* Output the font definitions for all fonts that were used */ - k = max_font_id(); - while (k > 0) { - if (font_used(k)) { - dvi_font_def(k); - } - decr(k); - } - - dvi_out(post_post); - dvi_four(last_bop); - dvi_out(id_byte); -#ifndef IPC - k = 4 + ((dvi_buf_size - dvi_ptr) % 4); /* the number of 223's */ -#else - k = 7 - ((3 + dvi_offset + dvi_ptr) % 4); /* the number of 223's */ -#endif - - while (k > 0) { - dvi_out(223); - decr(k); - } - /* Empty the last bytes out of |dvi_buf| */ - /* Here is how we clean out the buffer when \TeX\ is all through; |dvi_ptr| - will be a multiple of~4. */ - if (dvi_limit == half_buf) - write_dvi(half_buf, dvi_buf_size - 1); - if (dvi_ptr > 0) - write_dvi(0, dvi_ptr - 1); - - if (callback_id == 0) { - tprint_nl("Output written on "); - tprint(pdf->file_name); - tprint(" ("); - print_int(total_pages); - tprint(" page"); - if (total_pages != 1) - print_char('s'); - tprint(", "); - print_int(dvi_offset + dvi_ptr); - tprint(" bytes)."); - } else if (callback_id > 0) { - run_callback(callback_id, "->"); - } - close_file(pdf->file); - } -} |