src/runtime/search.c

   1 /*
   2  * This software is part of the SBCL system. See the README file for
   3  * more information.
   4  *
   5  * This software is derived from the CMU CL system, which was
   6  * written at Carnegie Mellon University and released into the
   7  * public domain. The software is in the public domain and is
   8  * provided with absolutely no warranty. See the COPYING and CREDITS
   9  * files for more information.
  10  */
  11
  12 #include <string.h>
  13
  14 #include "sbcl.h"
  15 #include "runtime.h"
  16 #include "os.h"
  17 #include "search.h"
  18 #include "thread.h"
  19 #include "genesis/primitive-objects.h"
  20
  21 boolean search_for_type(int type, lispobj **start, int *count)
  22 {
  23     lispobj obj;
  24
  25     while ((*count == -1 || (*count > 0)) &&
  26            is_valid_lisp_addr((os_vm_address_t)*start)) {
  27         obj = **start;
  28         if (*count != -1)
  29             *count -= 2;
  30
  31         if (widetag_of(obj) == type)
  32             return 1;
  33
  34         (*start) += 2;
  35     }
  36     return 0;
  37 }
  38
  39 static int strcmp_ucs4_ascii(uint32_t* a, char* b)
  40 {
  41   int i = 0;
  42
  43   // Lisp terminates UCS4 strings with NULL bytes - probably to no avail
  44   // since null-terminated UCS4 isn't a common convention for any foreign ABI -
  45   // but length has been pre-checked, so hitting an ASCII null is a win.
  46   while (a[i] == ((unsigned char*)b)[i])
  47     if (b[i] == 0)
  48       return 0;
  49     else
  50       ++i;
  51   return a[i] - b[i]; // same return convention as strcmp()
  52 }
  53
  54 boolean search_for_symbol(char *name, lispobj **start, int *count)
  55 {
  56     struct symbol *symbol;
  57     struct vector *symbol_name;
  58     int namelen = strlen(name);
  59
  60     while (search_for_type(SYMBOL_HEADER_WIDETAG, start, count)) {
  61         symbol = (struct symbol *)native_pointer((lispobj)*start);
  62         if (lowtag_of(symbol->name) == OTHER_POINTER_LOWTAG) {
  63             symbol_name = (struct vector *)native_pointer(symbol->name);
  64             if (is_valid_lisp_addr((os_vm_address_t)symbol_name) &&
  65                 /* FIXME: Broken with more than one type of string
  66                    (i.e. even broken given (VECTOR NIL) */
  67                 ((widetag_of(symbol_name->header) == SIMPLE_BASE_STRING_WIDETAG
  68                   && fixnum_value(symbol_name->length) == namelen
  69                   && !strcmp((char *)symbol_name->data, name))
  70 #ifdef LISP_FEATURE_SB_UNICODE
  71                  || (widetag_of(symbol_name->header) == SIMPLE_CHARACTER_STRING_WIDETAG
  72                      && fixnum_value(symbol_name->length) == namelen
  73                      && !strcmp_ucs4_ascii((uint32_t*)symbol_name->data, name))
  74 #endif
  75                  ))
  76                 return 1;
  77         }
  78         (*start) += 2;
  79     }
  80     return 0;
  81 }