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-rw-r--r--glpk-5.0/examples/tsp/misc.c159
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diff --git a/glpk-5.0/examples/tsp/misc.c b/glpk-5.0/examples/tsp/misc.c
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+/* misc.c */
+
+/* Written by Andrew Makhorin <mao@gnu.org>, October 2015. */
+
+#include <ctype.h>
+#include <float.h>
+#include <limits.h>
+#include <stdlib.h>
+#include "misc.h"
+
+/***********************************************************************
+* NAME
+*
+* str2int - convert character string to value of int type
+*
+* SYNOPSIS
+*
+* #include "misc.h"
+* int str2int(const char *str, int *val);
+*
+* DESCRIPTION
+*
+* The routine str2int converts the character string str to a value of
+* integer type and stores the value into location, which the parameter
+* val points to (in the case of error content of this location is not
+* changed).
+*
+* RETURNS
+*
+* The routine returns one of the following error codes:
+*
+* 0 - no error;
+* 1 - value out of range;
+* 2 - character string is syntactically incorrect. */
+
+int str2int(const char *str, int *val_)
+{ int d, k, s, val = 0;
+ /* scan optional sign */
+ if (str[0] == '+')
+ s = +1, k = 1;
+ else if (str[0] == '-')
+ s = -1, k = 1;
+ else
+ s = +1, k = 0;
+ /* check for the first digit */
+ if (!isdigit((unsigned char)str[k]))
+ return 2;
+ /* scan digits */
+ while (isdigit((unsigned char)str[k]))
+ { d = str[k++] - '0';
+ if (s > 0)
+ { if (val > INT_MAX / 10)
+ return 1;
+ val *= 10;
+ if (val > INT_MAX - d)
+ return 1;
+ val += d;
+ }
+ else /* s < 0 */
+ { if (val < INT_MIN / 10)
+ return 1;
+ val *= 10;
+ if (val < INT_MIN + d)
+ return 1;
+ val -= d;
+ }
+ }
+ /* check for terminator */
+ if (str[k] != '\0')
+ return 2;
+ /* conversion has been done */
+ *val_ = val;
+ return 0;
+}
+
+/***********************************************************************
+* NAME
+*
+* str2num - convert character string to value of double type
+*
+* SYNOPSIS
+*
+* #include "misc.h"
+* int str2num(const char *str, double *val);
+*
+* DESCRIPTION
+*
+* The routine str2num converts the character string str to a value of
+* double type and stores the value into location, which the parameter
+* val points to (in the case of error content of this location is not
+* changed).
+*
+* RETURNS
+*
+* The routine returns one of the following error codes:
+*
+* 0 - no error;
+* 1 - value out of range;
+* 2 - character string is syntactically incorrect. */
+
+int str2num(const char *str, double *val_)
+{ int k;
+ double val;
+ /* scan optional sign */
+ k = (str[0] == '+' || str[0] == '-' ? 1 : 0);
+ /* check for decimal point */
+ if (str[k] == '.')
+ { k++;
+ /* a digit should follow it */
+ if (!isdigit((unsigned char)str[k]))
+ return 2;
+ k++;
+ goto frac;
+ }
+ /* integer part should start with a digit */
+ if (!isdigit((unsigned char)str[k]))
+ return 2;
+ /* scan integer part */
+ while (isdigit((unsigned char)str[k]))
+ k++;
+ /* check for decimal point */
+ if (str[k] == '.') k++;
+frac: /* scan optional fraction part */
+ while (isdigit((unsigned char)str[k]))
+ k++;
+ /* check for decimal exponent */
+ if (str[k] == 'E' || str[k] == 'e')
+ { k++;
+ /* scan optional sign */
+ if (str[k] == '+' || str[k] == '-')
+ k++;
+ /* a digit should follow E, E+ or E- */
+ if (!isdigit((unsigned char)str[k]))
+ return 2;
+ }
+ /* scan optional exponent part */
+ while (isdigit((unsigned char)str[k]))
+ k++;
+ /* check for terminator */
+ if (str[k] != '\0')
+ return 2;
+ /* perform conversion */
+ { char *endptr;
+ val = strtod(str, &endptr);
+ if (*endptr != '\0')
+ return 2;
+ }
+ /* check for overflow */
+ if (!(-DBL_MAX <= val && val <= +DBL_MAX))
+ return 1;
+ /* check for underflow */
+ if (-DBL_MIN < val && val < +DBL_MIN)
+ val = 0.0;
+ /* conversion has been done */
+ *val_ = val;
+ return 0;
+}
+
+/* eof */