stdscan.c

   1 #include "compiler.h"
   2
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include <string.h>
   6 #include <ctype.h>
   7 #include <inttypes.h>
   8
   9 #include "nasm.h"
  10 #include "nasmlib.h"
  11 #include "stdscan.h"
  12 #include "insns.h"
  13
  14 /*
  15  * Standard scanner routine used by parser.c and some output
  16  * formats. It keeps a succession of temporary-storage strings in
  17  * stdscan_tempstorage, which can be cleared using stdscan_reset.
  18  */
  19 static char **stdscan_tempstorage = NULL;
  20 static int stdscan_tempsize = 0, stdscan_templen = 0;
  21 #define STDSCAN_TEMP_DELTA 256
  22
  23 static void stdscan_pop(void)
  24 {
  25     nasm_free(stdscan_tempstorage[--stdscan_templen]);
  26 }
  27
  28 void stdscan_reset(void)
  29 {
  30     while (stdscan_templen > 0)
  31         stdscan_pop();
  32 }
  33
  34 /*
  35  * Unimportant cleanup is done to avoid confusing people who are trying
  36  * to debug real memory leaks
  37  */
  38 void stdscan_cleanup(void)
  39 {
  40     stdscan_reset();
  41     nasm_free(stdscan_tempstorage);
  42 }
  43
  44 static char *stdscan_copy(char *p, int len)
  45 {
  46     char *text;
  47
  48     text = nasm_malloc(len + 1);
  49     strncpy(text, p, len);
  50     text[len] = '\0';
  51
  52     if (stdscan_templen >= stdscan_tempsize) {
  53         stdscan_tempsize += STDSCAN_TEMP_DELTA;
  54         stdscan_tempstorage = nasm_realloc(stdscan_tempstorage,
  55                                            stdscan_tempsize *
  56                                            sizeof(char *));
  57     }
  58     stdscan_tempstorage[stdscan_templen++] = text;
  59
  60     return text;
  61 }
  62
  63 char *stdscan_bufptr = NULL;
  64 int stdscan(void *private_data, struct tokenval *tv)
  65 {
  66     char ourcopy[MAX_KEYWORD + 1], *r, *s;
  67
  68     (void)private_data;         /* Don't warn that this parameter is unused */
  69
  70     while (isspace(*stdscan_bufptr))
  71         stdscan_bufptr++;
  72     if (!*stdscan_bufptr)
  73         return tv->t_type = 0;
  74
  75     /* we have a token; either an id, a number or a char */
  76     if (isidstart(*stdscan_bufptr) ||
  77         (*stdscan_bufptr == '$' && isidstart(stdscan_bufptr[1]))) {
  78         /* now we've got an identifier */
  79         bool is_sym = false;
  80
  81         if (*stdscan_bufptr == '$') {
  82             is_sym = true;
  83             stdscan_bufptr++;
  84         }
  85
  86         r = stdscan_bufptr++;
  87         /* read the entire buffer to advance the buffer pointer but... */
  88         while (isidchar(*stdscan_bufptr))
  89             stdscan_bufptr++;
  90
  91         /* ... copy only up to IDLEN_MAX-1 characters */
  92         tv->t_charptr = stdscan_copy(r, stdscan_bufptr - r < IDLEN_MAX ?
  93                                      stdscan_bufptr - r : IDLEN_MAX - 1);
  94
  95         if (is_sym || stdscan_bufptr - r > MAX_KEYWORD)
  96             return tv->t_type = TOKEN_ID;       /* bypass all other checks */
  97
  98         for (s = tv->t_charptr, r = ourcopy; *s; s++)
  99             *r++ = tolower(*s);
 100         *r = '\0';
 101         /* right, so we have an identifier sitting in temp storage. now,
 102          * is it actually a register or instruction name, or what? */
 103         return nasm_token_hash(ourcopy, tv);
 104     } else if (*stdscan_bufptr == '$' && !isnumchar(stdscan_bufptr[1])) {
 105         /*
 106          * It's a $ sign with no following hex number; this must
 107          * mean it's a Here token ($), evaluating to the current
 108          * assembly location, or a Base token ($$), evaluating to
 109          * the base of the current segment.
 110          */
 111         stdscan_bufptr++;
 112         if (*stdscan_bufptr == '$') {
 113             stdscan_bufptr++;
 114             return tv->t_type = TOKEN_BASE;
 115         }
 116         return tv->t_type = TOKEN_HERE;
 117     } else if (isnumstart(*stdscan_bufptr)) {   /* now we've got a number */
 118         int rn_error;
 119
 120         r = stdscan_bufptr++;
 121         while (isnumchar(*stdscan_bufptr))
 122             stdscan_bufptr++;
 123
 124         if (*stdscan_bufptr == '.') {
 125             /*
 126              * a floating point constant
 127              */
 128             stdscan_bufptr++;
 129             while (isnumchar(*stdscan_bufptr) ||
 130                    ((stdscan_bufptr[-1] == 'e'
 131                      || stdscan_bufptr[-1] == 'E'
 132                      || stdscan_bufptr[-1] == 'p'
 133                      || stdscan_bufptr[-1] == 'P')
 134                     && (*stdscan_bufptr == '-' || *stdscan_bufptr == '+'))) {
 135                 stdscan_bufptr++;
 136             }
 137             tv->t_charptr = stdscan_copy(r, stdscan_bufptr - r);
 138             return tv->t_type = TOKEN_FLOAT;
 139         }
 140         r = stdscan_copy(r, stdscan_bufptr - r);
 141         tv->t_integer = readnum(r, &rn_error);
 142         stdscan_pop();
 143         if (rn_error)
 144             return tv->t_type = TOKEN_ERRNUM;   /* some malformation occurred */
 145         tv->t_charptr = NULL;
 146         return tv->t_type = TOKEN_NUM;
 147     } else if (*stdscan_bufptr == '\'' || *stdscan_bufptr == '"') {     /* a char constant */
 148         char quote = *stdscan_bufptr++, *r;
 149         int rn_warn;
 150         r = tv->t_charptr = stdscan_bufptr;
 151         while (*stdscan_bufptr && *stdscan_bufptr != quote)
 152             stdscan_bufptr++;
 153         tv->t_inttwo = stdscan_bufptr - r;      /* store full version */
 154         if (!*stdscan_bufptr)
 155             return tv->t_type = TOKEN_ERRNUM;   /* unmatched quotes */
 156         stdscan_bufptr++;       /* skip over final quote */
 157         tv->t_integer = readstrnum(r, tv->t_inttwo, &rn_warn);
 158         /* FIXME: rn_warn is not checked! */
 159         return tv->t_type = TOKEN_NUM;
 160     } else if (*stdscan_bufptr == ';') {        /* a comment has happened - stay */
 161         return tv->t_type = 0;
 162     } else if (stdscan_bufptr[0] == '>' && stdscan_bufptr[1] == '>') {
 163         stdscan_bufptr += 2;
 164         return tv->t_type = TOKEN_SHR;
 165     } else if (stdscan_bufptr[0] == '<' && stdscan_bufptr[1] == '<') {
 166         stdscan_bufptr += 2;
 167         return tv->t_type = TOKEN_SHL;
 168     } else if (stdscan_bufptr[0] == '/' && stdscan_bufptr[1] == '/') {
 169         stdscan_bufptr += 2;
 170         return tv->t_type = TOKEN_SDIV;
 171     } else if (stdscan_bufptr[0] == '%' && stdscan_bufptr[1] == '%') {
 172         stdscan_bufptr += 2;
 173         return tv->t_type = TOKEN_SMOD;
 174     } else if (stdscan_bufptr[0] == '=' && stdscan_bufptr[1] == '=') {
 175         stdscan_bufptr += 2;
 176         return tv->t_type = TOKEN_EQ;
 177     } else if (stdscan_bufptr[0] == '<' && stdscan_bufptr[1] == '>') {
 178         stdscan_bufptr += 2;
 179         return tv->t_type = TOKEN_NE;
 180     } else if (stdscan_bufptr[0] == '!' && stdscan_bufptr[1] == '=') {
 181         stdscan_bufptr += 2;
 182         return tv->t_type = TOKEN_NE;
 183     } else if (stdscan_bufptr[0] == '<' && stdscan_bufptr[1] == '=') {
 184         stdscan_bufptr += 2;
 185         return tv->t_type = TOKEN_LE;
 186     } else if (stdscan_bufptr[0] == '>' && stdscan_bufptr[1] == '=') {
 187         stdscan_bufptr += 2;
 188         return tv->t_type = TOKEN_GE;
 189     } else if (stdscan_bufptr[0] == '&' && stdscan_bufptr[1] == '&') {
 190         stdscan_bufptr += 2;
 191         return tv->t_type = TOKEN_DBL_AND;
 192     } else if (stdscan_bufptr[0] == '^' && stdscan_bufptr[1] == '^') {
 193         stdscan_bufptr += 2;
 194         return tv->t_type = TOKEN_DBL_XOR;
 195     } else if (stdscan_bufptr[0] == '|' && stdscan_bufptr[1] == '|') {
 196         stdscan_bufptr += 2;
 197         return tv->t_type = TOKEN_DBL_OR;
 198     } else                      /* just an ordinary char */
 199         return tv->t_type = (uint8_t)(*stdscan_bufptr++);
 200 }
 201