clients/lib/strlib.c

   1 /*
   2 ** strlib.c
   3 ** String library to LUA
   4 */
   5
   6 char *rcs_strlib="$Id: strlib.c,v 1.12 1995/02/06 19:37:51 roberto Exp $";
   7
   8 #include <string.h>
   9 #include <stdlib.h>
  10 #include <ctype.h>
  11
  12 #include "lua.h"
  13 #include "lualib.h"
  14
  15
  16 static char *newstring (lua_Object o)
  17 {
  18   char *s = lua_getstring(o);
  19   char *ns = (char *)malloc(strlen(s)+1);
  20   if (ns == 0)
  21     lua_error("not enough memory for new string");
  22   strcpy(ns, s);
  23   return ns;
  24 }
  25
  26
  27 /*
  28 ** Return the position of the first caracter of a substring into a string
  29 ** LUA interface:
  30 **                      n = strfind (string, substring, init, end)
  31 */
  32 static void str_find (void)
  33 {
  34  char *s1, *s2, *f;
  35  int init;
  36  lua_Object o1 = lua_getparam (1);
  37  lua_Object o2 = lua_getparam (2);
  38  lua_Object o3 = lua_getparam (3);
  39  lua_Object o4 = lua_getparam (4);
  40  if (!lua_isstring(o1) || !lua_isstring(o2))
  41    lua_error ("incorrect arguments to function `strfind'");
  42  if (o3 == LUA_NOOBJECT)
  43   init = 0;
  44  else if (lua_isnumber(o3))
  45   init = lua_getnumber(o3)-1;
  46  else
  47  {
  48    lua_error ("incorrect arguments to function `strfind'");
  49    return;  /* to avoid warnings */
  50  }
  51  s1 = lua_getstring(o1);
  52  s2 = lua_getstring(o2);
  53  f = strstr(s1+init,s2);
  54  if (f != NULL)
  55  {
  56   int pos = f-s1+1;
  57   if (o4 == LUA_NOOBJECT)
  58    lua_pushnumber (pos);
  59   else if (!lua_isnumber(o4))
  60    lua_error ("incorrect arguments to function `strfind'");
  61   else if ((int)lua_getnumber(o4) >= pos+strlen(s2)-1)
  62    lua_pushnumber (pos);
  63   else
  64    lua_pushnil();
  65  }
  66  else
  67   lua_pushnil();
  68 }
  69
  70 /*
  71 ** Return the string length
  72 ** LUA interface:
  73 **                      n = strlen (string)
  74 */
  75 static void str_len (void)
  76 {
  77  lua_Object o = lua_getparam (1);
  78  if (!lua_isstring(o))
  79    lua_error ("incorrect arguments to function `strlen'");
  80  lua_pushnumber(strlen(lua_getstring(o)));
  81 }
  82
  83
  84 /*
  85 ** Return the substring of a string, from start to end
  86 ** LUA interface:
  87 **                      substring = strsub (string, start, end)
  88 */
  89 static void str_sub (void)
  90 {
  91  int start, end;
  92  char *s;
  93  lua_Object o1 = lua_getparam (1);
  94  lua_Object o2 = lua_getparam (2);
  95  lua_Object o3 = lua_getparam (3);
  96  if (!lua_isstring(o1) || !lua_isnumber(o2))
  97    lua_error ("incorrect arguments to function `strsub'");
  98  if (o3 != LUA_NOOBJECT && !lua_isnumber(o3))
  99    lua_error ("incorrect third argument to function `strsub'");
 100  s = newstring(o1);
 101  start = lua_getnumber (o2);
 102  end = o3 == LUA_NOOBJECT ? strlen(s) : lua_getnumber (o3);
 103  if (end < start || start < 1 || end > strlen(s))
 104   lua_pushliteral("");
 105  else
 106  {
 107   s[end] = 0;
 108   lua_pushstring (&s[start-1]);
 109  }
 110  free(s);
 111 }
 112
 113 /*
 114 ** Convert a string to lower case.
 115 ** LUA interface:
 116 **                      lowercase = strlower (string)
 117 */
 118 static void str_lower (void)
 119 {
 120  char *s, *c;
 121  lua_Object o = lua_getparam (1);
 122  if (!lua_isstring(o))
 123    lua_error ("incorrect arguments to function `strlower'");
 124  c = s = newstring(o);
 125  while (*c != 0)
 126  {
 127   *c = tolower(*c);
 128   c++;
 129  }
 130  lua_pushstring(s);
 131  free(s);
 132 }
 133
 134
 135 /*
 136 ** Convert a string to upper case.
 137 ** LUA interface:
 138 **                      uppercase = strupper (string)
 139 */
 140 static void str_upper (void)
 141 {
 142  char *s, *c;
 143  lua_Object o = lua_getparam (1);
 144  if (!lua_isstring(o))
 145    lua_error ("incorrect arguments to function `strlower'");
 146  c = s = newstring(o);
 147  while (*c != 0)
 148  {
 149   *c = toupper(*c);
 150   c++;
 151  }
 152  lua_pushstring(s);
 153  free(s);
 154 }
 155
 156
 157 /*
 158 ** Open string library
 159 */
 160 void strlib_open (void)
 161 {
 162  lua_register ("strfind", str_find);
 163  lua_register ("strlen", str_len);
 164  lua_register ("strsub", str_sub);
 165  lua_register ("strlower", str_lower);
 166  lua_register ("strupper", str_upper);
 167 }