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
  51 typedef struct {
  52     char **page_stack;
  53     char **form_stack;
  54     char *page_current;
  55     char *form_current;
  56     char *form_init;
  57     int page_size;
  58     int form_size;
  59     int page_used;
  60     int form_used;
  61     int literal_mode;
  62     boolean page_start;
  63 } colstack_type;
  64
  65 static colstack_type *colstacks = NULL;
  66 static int colstacks_size = 0;
  67 static int colstacks_used = 0;
  68
  69 @ Initialization is done, if the color stacks are used, |init_colorstacks()| is defined
  70 as macro to avoid unnecessary procedure calls.
  71
  72 @c
  73 #define init_colorstacks() if (colstacks_size == 0) colstacks_first_init();
  74
  75 static void colstacks_first_init(void)
  76 {
  77     colstacks_size = STACK_INCREMENT;
  78     colstacks = xtalloc((unsigned) colstacks_size, colstack_type);
  79     colstacks_used = 1;
  80     colstacks[0].page_stack = NULL;
  81     colstacks[0].form_stack = NULL;
  82     colstacks[0].page_size = 0;
  83     colstacks[0].form_size = 0;
  84     colstacks[0].page_used = 0;
  85     colstacks[0].form_used = 0;
  86     colstacks[0].page_current = xstrdup(COLOR_DEFAULT);
  87     colstacks[0].form_current = xstrdup(COLOR_DEFAULT);
  88     colstacks[0].form_init = xstrdup(COLOR_DEFAULT);
  89     colstacks[0].literal_mode = direct_always;
  90     colstacks[0].page_start = true;
  91 }
  92
  93 @ @c
  94 int colorstackused(void)
  95 {
  96     init_colorstacks();
  97     return colstacks_used;
  98 }
  99
 100 @   A new color stack is setup with the given parameters. The stack number is returned
 101 or -1 in case of error (no room).
 102
 103 @c
 104 int newcolorstack(const char *str, int literal_mode, boolean page_start)
 105 {
 106     colstack_type *colstack;
 107     int colstack_num;
 108     init_colorstacks();
 109     /* make room */
 110     if (colstacks_used == MAX_COLORSTACKS) {
 111         return -1;
 112     }
 113     if (colstacks_used == colstacks_size) {
 114         colstacks_size += STACK_INCREMENT;
 115         /*
 116             If |(MAX_COLORSTACKS mod STACK_INCREMENT = 0)| then we don't
 117             need to check the case that size overruns |MAX_COLORSTACKS|.
 118         */
 119         colstacks = xreallocarray(colstacks, colstack_type, (unsigned) colstacks_size);
 120     }
 121     /* claim new color stack */
 122     colstack_num = colstacks_used++;
 123     colstack = &colstacks[colstack_num];
 124     /* configure the new color stack */
 125     colstack->page_stack = NULL;
 126     colstack->form_stack = NULL;
 127     colstack->page_size = 0;
 128     colstack->page_used = 0;
 129     colstack->form_size = 0;
 130     colstack->form_used = 0;
 131     colstack->literal_mode = literal_mode;
 132     colstack->page_start = page_start;
 133     colstack->page_current = NULL;
 134     colstack->form_current = NULL;
 135     colstack->form_init = NULL;
 136     if (str) {
 137         colstack->page_current = xstrdup(str);
 138         colstack->form_current = xstrdup(str);
 139         colstack->form_init = xstrdup(str);
 140     }
 141     return colstack_num;
 142 }
 143
 144 @ @c
 145 #define get_colstack(n) (&colstacks[n])
 146
 147 @ Puts a string on top of the string pool and updates |pool_ptr|.
 148
 149 @c static void put_cstring_on_str_pool(char *str)
 150 {
 151     int save_selector = selector;
 152     selector = new_string;
 153     if (str == NULL || *str == 0) {
 154         return;
 155     }
 156     tprint(str);
 157     selector = save_selector;
 158 }
 159
 160 @ @c
 161 static int colorstackset(int colstack_no, str_number s)
 162 {
 163     colstack_type *colstack = get_colstack(colstack_no);
 164
 165     if (global_shipping_mode == SHIPPING_PAGE) {
 166         xfree(colstack->page_current);
 167         colstack->page_current = makecstring(s);
 168     } else {
 169         xfree(colstack->form_current);
 170         colstack->form_current = makecstring(s);
 171     }
 172     return colstack->literal_mode;
 173 }
 174
 175 @ @c
 176 int colorstackcurrent(int colstack_no)
 177 {
 178     colstack_type *colstack = get_colstack(colstack_no);
 179
 180     if (global_shipping_mode == SHIPPING_PAGE) {
 181         put_cstring_on_str_pool(colstack->page_current);
 182     } else {
 183         put_cstring_on_str_pool(colstack->form_current);
 184     }
 185     return colstack->literal_mode;
 186 }
 187
 188 @ @c
 189 static int colorstackpush(int colstack_no, str_number s)
 190 {
 191     colstack_type *colstack = get_colstack(colstack_no);
 192     char *str;
 193     if (global_shipping_mode == SHIPPING_PAGE) {
 194         if (colstack->page_used == colstack->page_size) {
 195             colstack->page_size += STACK_INCREMENT;
 196             xretalloc(colstack->page_stack, (unsigned) colstack->page_size, char *);
 197         }
 198         colstack->page_stack[colstack->page_used++] = colstack->page_current;
 199         str = makecstring(s);
 200         if (*str == 0) {
 201             colstack->page_current = NULL;
 202         } else {
 203             colstack->page_current = xstrdup(str);
 204         }
 205         free(str);
 206     } else {
 207         if (colstack->form_used == colstack->form_size) {
 208             colstack->form_size += STACK_INCREMENT;
 209             xretalloc(colstack->form_stack, (unsigned) colstack->form_size, char *);
 210         }
 211         colstack->form_stack[colstack->form_used++] = colstack->form_current;
 212         str = makecstring(s);
 213         if (*str == 0) {
 214             colstack->form_current = NULL;
 215         } else {
 216             colstack->form_current = xstrdup(str);
 217         }
 218         free(str);
 219     }
 220     return colstack->literal_mode;
 221 }
 222
 223 @ @c
 224 int colorstackpop(int colstack_no)
 225 {
 226     colstack_type *colstack = get_colstack(colstack_no);
 227     if (global_shipping_mode == SHIPPING_PAGE) {
 228         if (colstack->page_used == 0) {
 229             formatted_warning("pdf backend","pop empty color page stack %u",(unsigned int) colstack_no);
 230             return colstack->literal_mode;
 231         }
 232         xfree(colstack->page_current);
 233         colstack->page_current = colstack->page_stack[--colstack->page_used];
 234         put_cstring_on_str_pool(colstack->page_current);
 235     } else {
 236         if (colstack->form_used == 0) {
 237             formatted_warning("pdf backend","pop empty color form stack %u",(unsigned int) colstack_no);
 238             return colstack->literal_mode;
 239         }
 240         xfree(colstack->form_current);
 241         colstack->form_current = colstack->form_stack[--colstack->form_used];
 242         put_cstring_on_str_pool(colstack->form_current);
 243     }
 244     return colstack->literal_mode;
 245 }
 246
 247 @ @c
 248 void colorstackpagestart(void)
 249 {
 250     int i, j;
 251     colstack_type *colstack;
 252     if (global_shipping_mode == SHIPPING_PAGE) {
 253         /* see procedure |pdf_out_colorstack_startpage| */
 254         return;
 255     }
 256
 257     for (i = 0; i < colstacks_used; i++) {
 258         colstack = &colstacks[i];
 259         for (j = 0; j < colstack->form_used; j++) {
 260             xfree(colstack->form_stack[j]);
 261         }
 262         colstack->form_used = 0;
 263         xfree(colstack->form_current);
 264         if (colstack->form_init == NULL) {
 265             colstack->form_current = NULL;
 266         } else {
 267             colstack->form_current = xstrdup(colstack->form_init);
 268         }
 269     }
 270 }
 271
 272 @ @c
 273 int colorstackskippagestart(int colstack_no)
 274 {
 275     colstack_type *colstack = get_colstack(colstack_no);
 276     if (!colstack->page_start) {
 277         return 1;
 278     }
 279     if (colstack->page_current == NULL) {
 280         return 0;
 281     }
 282     if (strcmp(COLOR_DEFAULT, colstack->page_current) == 0) {
 283         return 2;
 284     }
 285     return 0;
 286 }
 287
 288
 289 @ @c
 290 void pdf_out_colorstack(PDF pdf, halfword p)
 291 {
 292     int old_setting;
 293     str_number s;
 294     int cmd = pdf_colorstack_cmd(p);
 295     int stack_no = pdf_colorstack_stack(p);
 296     int literal_mode = 0;
 297     if (stack_no >= colorstackused()) {
 298         tprint_nl("");
 299         tprint("Color stack ");
 300         print_int(stack_no);
 301         tprint(" is not initialized for use!");
 302         tprint_nl("");
 303         return;
 304     }
 305     switch (cmd) {
 306         case colorstack_set:
 307         case colorstack_push:
 308             old_setting = selector;
 309             selector = new_string;
 310             show_token_list(token_link(pdf_colorstack_data(p)), null, -1);
 311             selector = old_setting;
 312             s = make_string();
 313             if (cmd == colorstack_set)
 314                 literal_mode = colorstackset(stack_no, s);
 315             else
 316                 literal_mode = colorstackpush(stack_no, s);
 317             if (str_length(s) > 0)
 318                 pdf_literal(pdf, s, literal_mode, false);
 319             flush_str(s);
 320             return;
 321             break;
 322         case colorstack_pop:
 323             literal_mode = colorstackpop(stack_no);
 324             break;
 325         case colorstack_current:
 326             literal_mode = colorstackcurrent(stack_no);
 327             break;
 328         default:
 329             break;
 330     }
 331     if (cur_length > 0) {
 332         s = make_string();
 333         pdf_literal(pdf, s, literal_mode, false);
 334         flush_str(s);
 335     }
 336 }
 337
 338 @ @c
 339 void pdf_out_colorstack_startpage(PDF pdf)
 340 {
 341     int start_status;
 342     int literal_mode;
 343     str_number s;
 344     int i = 0;
 345     int max = colorstackused();
 346     while (i < max) {
 347         start_status = colorstackskippagestart(i);
 348         if (start_status == 0) {
 349             literal_mode = colorstackcurrent(i);
 350             if (cur_length > 0) {
 351                 s = make_string();
 352                 pdf_literal(pdf, s, literal_mode, false);
 353                 flush_str(s);
 354             }
 355         }
 356         i++;
 357     }
 358 }