lang/cem/cemcom/skip.c

   1 /*
   2  * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
   3  * See the copyright notice in the ACK home directory, in the file "Copyright".
   4  */
   5 /* $Id: skip.c,v 3.8 1994/06/24 12:05:55 ceriel Exp $ */
   6 /* PREPROCESSOR: INPUT SKIP FUNCTIONS */
   7
   8 #include        "nopp.h"
   9 #include        "arith.h"
  10 #include        "LLlex.h"
  11 #include        "class.h"
  12 #include        "input.h"
  13 #include        "interface.h"
  14
  15 #ifndef NOPP
  16 int
  17 skipspaces(ch, skipnl)
  18         register int ch;
  19 {
  20         /*      skipspaces() skips any white space and returns the first
  21                 non-space character.
  22         */
  23         register int nlseen = 0;
  24
  25         for (;;) {
  26                 while (class(ch) == STSKIP) {
  27                         nlseen = 0;
  28                         LoadChar(ch);
  29                 }
  30                 if (skipnl && class(ch) == STNL) {
  31                         LoadChar(ch);
  32                         LineNumber++;
  33                         nlseen++;
  34                         continue;
  35                 }
  36                 /* How about "\\\n"?????????    */
  37
  38                 if (ch == '/') {
  39                         LoadChar(ch);
  40                         if (ch == '*') {
  41                                 skipcomment();
  42                                 LoadChar(ch);
  43                         }
  44                         else    {
  45                                 PushBack();
  46                                 return '/';
  47                         }
  48                 }
  49                 else if (nlseen && ch == '#') {
  50                         domacro();
  51                         LoadChar(ch);
  52                         /* ch is the first character of a line. This means
  53                          * that nlseen will still be true.
  54                          */
  55                 } else
  56                         return ch;
  57         }
  58 }
  59 #endif /* NOPP */
  60
  61 skipline()
  62 {
  63         /*      skipline() skips all characters until a newline character
  64                 is seen, not escaped by a '\\'.
  65                 Any comment is skipped.
  66         */
  67         register int c;
  68
  69         LoadChar(c);
  70         while (class(c) != STNL && c != EOI) {
  71                 if (class(c) == STSTR || class(c) == STCHAR) {
  72                         register int stopc = c;
  73                         int escaped;
  74                         do {
  75                                 escaped = 0;
  76                                 LoadChar(c);
  77                                 if (class(c) == STNL || c == EOI) {
  78                                         break;
  79                                 }
  80                                 if (c == '\\') {
  81                                         LoadChar(c);
  82                                         if (c == '\n') {
  83                                                 ++LineNumber;
  84                                         }
  85                                         else escaped = 1;
  86                                 }
  87                         } while (escaped || c != stopc);
  88                         if (class(c) != STNL && c != EOI) {
  89                                 LoadChar(c);
  90                         }
  91                         continue;
  92                 }
  93                 if (c == '\\') {
  94                         LoadChar(c);
  95                         if (class(c) == STNL)
  96                                 ++LineNumber;
  97                 }
  98                 if (c == '/') {
  99                         LoadChar(c);
 100                         if (c == '*')
 101                                 skipcomment();
 102                         else
 103                                 continue;
 104                 }
 105                 LoadChar(c);
 106         }
 107         ++LineNumber;
 108
 109         if (c == EOI) {         /* garbage input...             */
 110                 lexerror("unexpected EOF while skipping text");
 111                 PushBack();
 112         }
 113 }