source/texk/web2c/luatexdir/pdf/pdfcolorstack.w

   1 % pdfcolorstack.w
   2 %
   3 % Copyright 2009-2011 Taco Hoekwater <taco@@luatex.org>
   4 %
   5 % This file is part of LuaTeX.
   6 %
   7 % LuaTeX is free software; you can redistribute it and/or modify it under
   8 % the terms of the GNU General Public License as published by the Free
   9 % Software Foundation; either version 2 of the License, or (at your
  10 % option) any later version.
  11 %
  12 % LuaTeX is distributed in the hope that it will be useful, but WITHOUT
  13 % ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 % FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  15 % License for more details.
  16 %
  17 % You should have received a copy of the GNU General Public License along
  18 % with LuaTeX; if not, see <http://www.gnu.org/licenses/>.
  19
  20 @ @c
  21
  22 #include "ptexlib.h"
  23
  24 @* Color Stack and Matrix Transformation Support.
  25
  26 @ In the following array and especially stack data structures are used.
  27
  28 They have the following properties:
  29
  30 \item{-} They automatically grow dynamically.
  31 \item{-} The size never decreases.
  32 \item{-} The variable with name ending in "size" contains the number how many
  33     entries the data structure can hold.
  34 \item{-} The variable with name ending in "used" contains the number of
  35     actually used entries.
  36 \item{-} Memory of strings in stack entries must be allocated and
  37     freed if the stack is cleared.
  38
  39 @ Color Stack
  40 @c
  41
  42 #define MAX_COLORSTACKS 32768
  43
  44 /*
  45     The colorstack number is stored in two bytes (info field of the node);
  46     condition (newcolorstack): |MAX_COLORSTACKS mod STACK_INCREMENT = 0|
  47 */
  48
  49 #define COLOR_DEFAULT "0 g 0 G"
  50 #define SET_ORIGIN    0
  51 #define DIRECT_PAGE   1
  52 #define DIRECT_ALWAYS 2
  53
  54 typedef struct {
  55     char **page_stack;
  56     char **form_stack;
  57     char *page_current;
  58     char *form_current;
  59     char *form_init;
  60     int page_size;
  61     int form_size;
  62     int page_used;
  63     int form_used;
  64     int literal_mode;
  65     boolean page_start;
  66 } colstack_type;
  67
  68 static colstack_type *colstacks = NULL;
  69 static int colstacks_size = 0;
  70 static int colstacks_used = 0;
  71
  72 @ Initialization is done, if the color stacks are used, |init_colorstacks()| is defined
  73 as macro to avoid unnecessary procedure calls.
  74
  75 @c
  76 #define init_colorstacks() if (colstacks_size == 0) colstacks_first_init();
  77
  78 static void colstacks_first_init(void)
  79 {
  80     colstacks_size = STACK_INCREMENT;
  81     colstacks = xtalloc((unsigned) colstacks_size, colstack_type);
  82     colstacks_used = 1;
  83     colstacks[0].page_stack = NULL;
  84     colstacks[0].form_stack = NULL;
  85     colstacks[0].page_size = 0;
  86     colstacks[0].form_size = 0;
  87     colstacks[0].page_used = 0;
  88     colstacks[0].form_used = 0;
  89     colstacks[0].page_current = xstrdup(COLOR_DEFAULT);
  90     colstacks[0].form_current = xstrdup(COLOR_DEFAULT);
  91     colstacks[0].form_init = xstrdup(COLOR_DEFAULT);
  92     colstacks[0].literal_mode = DIRECT_ALWAYS;
  93     colstacks[0].page_start = true;
  94 }
  95
  96 @ @c
  97 int colorstackused(void)
  98 {
  99     init_colorstacks();
 100     return colstacks_used;
 101 }
 102
 103 @   A new color stack is setup with the given parameters. The stack number is returned
 104 or -1 in case of error (no room).
 105
 106 @c
 107 int newcolorstack(const char *str, int literal_mode, boolean page_start)
 108 {
 109     colstack_type *colstack;
 110     int colstack_num;
 111     init_colorstacks();
 112     /* make room */
 113     if (colstacks_used == MAX_COLORSTACKS) {
 114         return -1;
 115     }
 116     if (colstacks_used == colstacks_size) {
 117         colstacks_size += STACK_INCREMENT;
 118         /*
 119             If |(MAX_COLORSTACKS mod STACK_INCREMENT = 0)| then we don't
 120             need to check the case that size overruns |MAX_COLORSTACKS|.
 121         */
 122         colstacks = xreallocarray(colstacks, colstack_type, (unsigned) colstacks_size);
 123     }
 124     /* claim new color stack */
 125     colstack_num = colstacks_used++;
 126     colstack = &colstacks[colstack_num];
 127     /* configure the new color stack */
 128     colstack->page_stack = NULL;
 129     colstack->form_stack = NULL;
 130     colstack->page_size = 0;
 131     colstack->page_used = 0;
 132     colstack->form_size = 0;
 133     colstack->form_used = 0;
 134     colstack->literal_mode = literal_mode;
 135     colstack->page_start = page_start;
 136     colstack->page_current = NULL;
 137     colstack->form_current = NULL;
 138     colstack->form_init = NULL;
 139     if (str) {
 140         colstack->page_current = xstrdup(str);
 141         colstack->form_current = xstrdup(str);
 142         colstack->form_init = xstrdup(str);
 143     }
 144     return colstack_num;
 145 }
 146
 147 @ @c
 148 #define get_colstack(n) (&colstacks[n])
 149
 150 @ Puts a string on top of the string pool and updates |pool_ptr|.
 151
 152 @c static void put_cstring_on_str_pool(char *str)
 153 {
 154     int save_selector = selector;
 155     selector = new_string;
 156     if (str == NULL || *str == 0) {
 157         return;
 158     }
 159     tprint(str);
 160     selector = save_selector;
 161 }
 162
 163 @ @c
 164 static int colorstackset(int colstack_no, str_number s)
 165 {
 166     colstack_type *colstack = get_colstack(colstack_no);
 167
 168     if (global_shipping_mode == SHIPPING_PAGE) {
 169         xfree(colstack->page_current);
 170         colstack->page_current = makecstring(s);
 171     } else {
 172         xfree(colstack->form_current);
 173         colstack->form_current = makecstring(s);
 174     }
 175     return colstack->literal_mode;
 176 }
 177
 178 @ @c
 179 int colorstackcurrent(int colstack_no)
 180 {
 181     colstack_type *colstack = get_colstack(colstack_no);
 182
 183     if (global_shipping_mode == SHIPPING_PAGE) {
 184         put_cstring_on_str_pool(colstack->page_current);
 185     } else {
 186         put_cstring_on_str_pool(colstack->form_current);
 187     }
 188     return colstack->literal_mode;
 189 }
 190
 191 @ @c
 192 static int colorstackpush(int colstack_no, str_number s)
 193 {
 194     colstack_type *colstack = get_colstack(colstack_no);
 195     char *str;
 196     if (global_shipping_mode == SHIPPING_PAGE) {
 197         if (colstack->page_used == colstack->page_size) {
 198             colstack->page_size += STACK_INCREMENT;
 199             xretalloc(colstack->page_stack, (unsigned) colstack->page_size, char *);
 200         }
 201         colstack->page_stack[colstack->page_used++] = colstack->page_current;
 202         str = makecstring(s);
 203         if (*str == 0) {
 204             colstack->page_current = NULL;
 205         } else {
 206             colstack->page_current = xstrdup(str);
 207         }
 208         free(str);
 209     } else {
 210         if (colstack->form_used == colstack->form_size) {
 211             colstack->form_size += STACK_INCREMENT;
 212             xretalloc(colstack->form_stack, (unsigned) colstack->form_size, char *);
 213         }
 214         colstack->form_stack[colstack->form_used++] = colstack->form_current;
 215         str = makecstring(s);
 216         if (*str == 0) {
 217             colstack->form_current = NULL;
 218         } else {
 219             colstack->form_current = xstrdup(str);
 220         }
 221         free(str);
 222     }
 223     return colstack->literal_mode;
 224 }
 225
 226 @ @c
 227 int colorstackpop(int colstack_no)
 228 {
 229     colstack_type *colstack = get_colstack(colstack_no);
 230     if (global_shipping_mode == SHIPPING_PAGE) {
 231         if (colstack->page_used == 0) {
 232             formatted_warning("pdf backend","pop empty color page stack %u",(unsigned int) colstack_no);
 233             return colstack->literal_mode;
 234         }
 235         xfree(colstack->page_current);
 236         colstack->page_current = colstack->page_stack[--colstack->page_used];
 237         put_cstring_on_str_pool(colstack->page_current);
 238     } else {
 239         if (colstack->form_used == 0) {
 240             formatted_warning("pdf backend","pop empty color form stack %u",(unsigned int) colstack_no);
 241             return colstack->literal_mode;
 242         }
 243         xfree(colstack->form_current);
 244         colstack->form_current = colstack->form_stack[--colstack->form_used];
 245         put_cstring_on_str_pool(colstack->form_current);
 246     }
 247     return colstack->literal_mode;
 248 }
 249
 250 @ @c
 251 void colorstackpagestart(void)
 252 {
 253     int i, j;
 254     colstack_type *colstack;
 255     if (global_shipping_mode == SHIPPING_PAGE) {
 256         /* see procedure |pdf_out_colorstack_startpage| */
 257         return;
 258     }
 259
 260     for (i = 0; i < colstacks_used; i++) {
 261         colstack = &colstacks[i];
 262         for (j = 0; j < colstack->form_used; j++) {
 263             xfree(colstack->form_stack[j]);
 264         }
 265         colstack->form_used = 0;
 266         xfree(colstack->form_current);
 267         if (colstack->form_init == NULL) {
 268             colstack->form_current = NULL;
 269         } else {
 270             colstack->form_current = xstrdup(colstack->form_init);
 271         }
 272     }
 273 }
 274
 275 @ @c
 276 int colorstackskippagestart(int colstack_no)
 277 {
 278     colstack_type *colstack = get_colstack(colstack_no);
 279     if (!colstack->page_start) {
 280         return 1;
 281     }
 282     if (colstack->page_current == NULL) {
 283         return 0;
 284     }
 285     if (strcmp(COLOR_DEFAULT, colstack->page_current) == 0) {
 286         return 2;
 287     }
 288     return 0;
 289 }
 290
 291
 292 @ @c
 293 void pdf_out_colorstack(PDF pdf, halfword p)
 294 {
 295     int old_setting;
 296     str_number s;
 297     int cmd = pdf_colorstack_cmd(p);
 298     int stack_no = pdf_colorstack_stack(p);
 299     int literal_mode = 0;
 300     if (stack_no >= colorstackused()) {
 301         tprint_nl("");
 302         tprint("Color stack ");
 303         print_int(stack_no);
 304         tprint(" is not initialized for use!");
 305         tprint_nl("");
 306         return;
 307     }
 308     switch (cmd) {
 309         case colorstack_set:
 310         case colorstack_push:
 311             old_setting = selector;
 312             selector = new_string;
 313             show_token_list(token_link(pdf_colorstack_data(p)), null, -1);
 314             selector = old_setting;
 315             s = make_string();
 316             if (cmd == colorstack_set)
 317                 literal_mode = colorstackset(stack_no, s);
 318             else
 319                 literal_mode = colorstackpush(stack_no, s);
 320             if (str_length(s) > 0)
 321                 pdf_literal(pdf, s, literal_mode, false);
 322             flush_str(s);
 323             return;
 324             break;
 325         case colorstack_pop:
 326             literal_mode = colorstackpop(stack_no);
 327             break;
 328         case colorstack_current:
 329             literal_mode = colorstackcurrent(stack_no);
 330             break;
 331         default:
 332             break;
 333     }
 334     if (cur_length > 0) {
 335         s = make_string();
 336         pdf_literal(pdf, s, literal_mode, false);
 337         flush_str(s);
 338     }
 339 }
 340
 341 @ @c
 342 void pdf_out_colorstack_startpage(PDF pdf)
 343 {
 344     int start_status;
 345     int literal_mode;
 346     str_number s;
 347     int i = 0;
 348     int max = colorstackused();
 349     while (i < max) {
 350         start_status = colorstackskippagestart(i);
 351         if (start_status == 0) {
 352             literal_mode = colorstackcurrent(i);
 353             if (cur_length > 0) {
 354                 s = make_string();
 355                 pdf_literal(pdf, s, literal_mode, false);
 356                 flush_str(s);
 357             }
 358         }
 359         i++;
 360     }
 361 }