diff jansson/src/strconv.c @ 0:0047655db1aa

jansson: import 2.7
author David Demelier <markand@malikania.fr>
date Wed, 24 Feb 2016 20:50:05 +0100
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jansson/src/strconv.c	Wed Feb 24 20:50:05 2016 +0100
@@ -0,0 +1,138 @@
+#include <assert.h>
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <math.h>
+#include "jansson_private.h"
+#include "strbuffer.h"
+
+/* need jansson_private_config.h to get the correct snprintf */
+#ifdef HAVE_CONFIG_H
+#include <jansson_private_config.h>
+#endif
+
+#if JSON_HAVE_LOCALECONV
+#include <locale.h>
+
+/*
+  - This code assumes that the decimal separator is exactly one
+    character.
+
+  - If setlocale() is called by another thread between the call to
+    localeconv() and the call to sprintf() or strtod(), the result may
+    be wrong. setlocale() is not thread-safe and should not be used
+    this way. Multi-threaded programs should use uselocale() instead.
+*/
+
+static void to_locale(strbuffer_t *strbuffer)
+{
+    const char *point;
+    char *pos;
+
+    point = localeconv()->decimal_point;
+    if(*point == '.') {
+        /* No conversion needed */
+        return;
+    }
+
+    pos = strchr(strbuffer->value, '.');
+    if(pos)
+        *pos = *point;
+}
+
+static void from_locale(char *buffer)
+{
+    const char *point;
+    char *pos;
+
+    point = localeconv()->decimal_point;
+    if(*point == '.') {
+        /* No conversion needed */
+        return;
+    }
+
+    pos = strchr(buffer, *point);
+    if(pos)
+        *pos = '.';
+}
+#endif
+
+int jsonp_strtod(strbuffer_t *strbuffer, double *out)
+{
+    double value;
+    char *end;
+
+#if JSON_HAVE_LOCALECONV
+    to_locale(strbuffer);
+#endif
+
+    errno = 0;
+    value = strtod(strbuffer->value, &end);
+    assert(end == strbuffer->value + strbuffer->length);
+
+    if((value == HUGE_VAL || value == -HUGE_VAL) && errno == ERANGE) {
+        /* Overflow */
+        return -1;
+    }
+
+    *out = value;
+    return 0;
+}
+
+int jsonp_dtostr(char *buffer, size_t size, double value, int precision)
+{
+    int ret;
+    char *start, *end;
+    size_t length;
+
+    if (precision == 0)
+        precision = 17;
+
+    ret = snprintf(buffer, size, "%.*g", precision, value);
+    if(ret < 0)
+        return -1;
+
+    length = (size_t)ret;
+    if(length >= size)
+        return -1;
+
+#if JSON_HAVE_LOCALECONV
+    from_locale(buffer);
+#endif
+
+    /* Make sure there's a dot or 'e' in the output. Otherwise
+       a real is converted to an integer when decoding */
+    if(strchr(buffer, '.') == NULL &&
+       strchr(buffer, 'e') == NULL)
+    {
+        if(length + 3 >= size) {
+            /* No space to append ".0" */
+            return -1;
+        }
+        buffer[length] = '.';
+        buffer[length + 1] = '0';
+        buffer[length + 2] = '\0';
+        length += 2;
+    }
+
+    /* Remove leading '+' from positive exponent. Also remove leading
+       zeros from exponents (added by some printf() implementations) */
+    start = strchr(buffer, 'e');
+    if(start) {
+        start++;
+        end = start + 1;
+
+        if(*start == '-')
+            start++;
+
+        while(*end == '0')
+            end++;
+
+        if(end != start) {
+            memmove(start, end, length - (size_t)(end - buffer));
+            length -= (size_t)(end - start);
+        }
+    }
+
+    return (int)length;
+}