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-rw-r--r--stdlib/strtol.c189
1 files changed, 189 insertions, 0 deletions
diff --git a/stdlib/strtol.c b/stdlib/strtol.c
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+++ b/stdlib/strtol.c
@@ -0,0 +1,189 @@
+/* Copyright (C) 1991, 1992, 1994, 1995 Free Software Foundation, Inc.
+
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <ctype.h>
+#include <limits.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <errno.h>
+
+/* Nonzero if we are defining `strtoul' or `strtouq', operating on unsigned
+   integers.  */
+#ifndef	UNSIGNED
+#define	UNSIGNED	0
+#endif
+
+/* If QUAD is defined, we are defining `strtoq' or `strtouq',
+   operating on `long long int's.  */
+#ifdef QUAD
+#if UNSIGNED
+#define strtoul		strtouq
+#else
+#define strtol		strtoq
+#endif
+#define	LONG		long long
+#undef	LONG_MIN
+#define	LONG_MIN	LONG_LONG_MIN
+#undef	LONG_MAX
+#define LONG_MAX	LONG_LONG_MAX
+#undef	ULONG_MAX
+#define ULONG_MAX	ULONG_LONG_MAX
+#if __GNUC__ == 2 && __GNUC_MINOR__ < 7
+/* Work around gcc bug with using this constant.  */
+static const unsigned long long int maxquad = ULONG_LONG_MAX;
+#undef	ULONG_MAX
+#define ULONG_MAX	maxquad
+#endif
+#else
+#define	LONG	long
+#endif
+
+/* Convert NPTR to an `unsigned long int' or `long int' in base BASE.
+   If BASE is 0 the base is determined by the presence of a leading
+   zero, indicating octal or a leading "0x" or "0X", indicating hexadecimal.
+   If BASE is < 2 or > 36, it is reset to 10.
+   If ENDPTR is not NULL, a pointer to the character after the last
+   one converted is stored in *ENDPTR.  */
+#if	UNSIGNED
+unsigned LONG int
+#define	strtol	strtoul
+#else
+LONG int
+#endif
+strtol (nptr, endptr, base)
+     const char *nptr;
+     char **endptr;
+     int base;
+{
+  int negative;
+  register unsigned LONG int cutoff;
+  register unsigned int cutlim;
+  register unsigned LONG int i;
+  register const char *s;
+  register unsigned char c;
+  const char *save;
+  int overflow;
+
+  if (base < 0 || base == 1 || base > 36)
+    base = 10;
+
+  s = nptr;
+
+  /* Skip white space.  */
+  while (isspace (*s))
+    ++s;
+  if (*s == '\0')
+    goto noconv;
+
+  /* Check for a sign.  */
+  if (*s == '-')
+    {
+      negative = 1;
+      ++s;
+    }
+  else if (*s == '+')
+    {
+      negative = 0;
+      ++s;
+    }
+  else
+    negative = 0;
+
+  if (base == 16 && s[0] == '0' && toupper (s[1]) == 'X')
+    s += 2;
+
+  /* If BASE is zero, figure it out ourselves.  */
+  if (base == 0)
+    if (*s == '0')
+      {
+	if (toupper (s[1]) == 'X')
+	  {
+	    s += 2;
+	    base = 16;
+	  }
+	else
+	  base = 8;
+      }
+    else
+      base = 10;
+
+  /* Save the pointer so we can check later if anything happened.  */
+  save = s;
+
+  cutoff = ULONG_MAX / (unsigned LONG int) base;
+  cutlim = ULONG_MAX % (unsigned LONG int) base;
+
+  overflow = 0;
+  i = 0;
+  for (c = *s; c != '\0'; c = *++s)
+    {
+      if (isdigit (c))
+	c -= '0';
+      else if (isalpha (c))
+	c = toupper (c) - 'A' + 10;
+      else
+	break;
+      if (c >= base)
+	break;
+      /* Check for overflow.  */
+      if (i > cutoff || (i == cutoff && c > cutlim))
+	overflow = 1;
+      else
+	{
+	  i *= (unsigned LONG int) base;
+	  i += c;
+	}
+    }
+
+  /* Check if anything actually happened.  */
+  if (s == save)
+    goto noconv;
+
+  /* Store in ENDPTR the address of one character
+     past the last character we converted.  */
+  if (endptr != NULL)
+    *endptr = (char *) s;
+
+#if	!UNSIGNED
+  /* Check for a value that is within the range of
+     `unsigned LONG int', but outside the range of `LONG int'.  */
+  if (i > (negative ?
+	   -(unsigned LONG int) LONG_MIN : (unsigned LONG int) LONG_MAX))
+    overflow = 1;
+#endif
+
+  if (overflow)
+    {
+      errno = ERANGE;
+#if	UNSIGNED
+      return ULONG_MAX;
+#else
+      return negative ? LONG_MIN : LONG_MAX;
+#endif
+    }
+
+  /* Return the result of the appropriate sign.  */
+  return (negative ? -i : i);
+
+noconv:
+  /* There was no number to convert.  */
+  if (endptr != NULL)
+    *endptr = (char *) nptr;
+  return 0L;
+}