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Use strtoll to parse ints

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This commit is contained in:
Jason King
2017-09-07 17:21:14 +00:00
parent e1561ed1df
commit 5355d387e9
1 changed files with 7 additions and 114 deletions
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121
json_util.c
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@@ -57,10 +57,6 @@
#include "json_tokener.h" #include "json_tokener.h"
#include "json_util.h" #include "json_util.h"
static int sscanf_is_broken = 0;
static int sscanf_is_broken_testdone = 0;
static void sscanf_is_broken_test(void);
static int _json_object_to_fd(int fd, struct json_object *obj, int flags, const char *filename); static int _json_object_to_fd(int fd, struct json_object *obj, int flags, const char *filename);
static char _last_err[256] = ""; static char _last_err[256] = "";
@@ -195,119 +191,16 @@ int json_parse_double(const char *buf, double *retval)
return end == buf ? 1 : 0; return end == buf ? 1 : 0;
} }
/*
* Not all implementations of sscanf actually work properly.
* Check whether the one we're currently using does, and if
* it's broken, enable the workaround code.
*/
static void sscanf_is_broken_test()
{
int64_t num64;
int ret_errno, is_int64_min, ret_errno2, is_int64_max;
(void)sscanf(" -01234567890123456789012345", "%" SCNd64, &num64);
ret_errno = errno;
is_int64_min = (num64 == INT64_MIN);
(void)sscanf(" 01234567890123456789012345", "%" SCNd64, &num64);
ret_errno2 = errno;
is_int64_max = (num64 == INT64_MAX);
if (ret_errno != ERANGE || !is_int64_min ||
ret_errno2 != ERANGE || !is_int64_max)
{
MC_DEBUG("sscanf_is_broken_test failed, enabling workaround code\n");
sscanf_is_broken = 1;
}
}
int json_parse_int64(const char *buf, int64_t *retval) int json_parse_int64(const char *buf, int64_t *retval)
{ {
int64_t num64; char *end = NULL;
const char *buf_sig_digits; int64_t val;
int orig_has_neg;
int saved_errno;
if (!sscanf_is_broken_testdone) errno = 0;
{ val = strtoll(buf, &end, 10);
sscanf_is_broken_test(); if (end != buf)
sscanf_is_broken_testdone = 1; *retval = val;
} return ((val == 0 && errno != 0) || (end == buf)) ? 1 : 0;
// Skip leading spaces
while (isspace((int)*buf) && *buf)
buf++;
errno = 0; // sscanf won't always set errno, so initialize
if (sscanf(buf, "%" SCNd64, &num64) != 1)
{
MC_DEBUG("Failed to parse, sscanf != 1\n");
return 1;
}
saved_errno = errno;
buf_sig_digits = buf;
orig_has_neg = 0;
if (*buf_sig_digits == '-')
{
buf_sig_digits++;
orig_has_neg = 1;
}
// Not all sscanf implementations actually work
if (sscanf_is_broken && saved_errno != ERANGE)
{
char buf_cmp[100];
char *buf_cmp_start = buf_cmp;
int recheck_has_neg = 0;
int buf_cmp_len;
// Skip leading zeros, but keep at least one digit
while (buf_sig_digits[0] == '0' && buf_sig_digits[1] != '\0')
buf_sig_digits++;
// Can't check num64==0 because some sscanf impl's parse
// non-zero values to 0. (e.g. Illumos with UINT64_MAX)
if (buf_sig_digits[0] == '0' && buf_sig_digits[1] == '\0')
orig_has_neg = 0; // "-0" is the same as just plain "0"
snprintf(buf_cmp_start, sizeof(buf_cmp), "%" PRId64, num64);
if (*buf_cmp_start == '-')
{
recheck_has_neg = 1;
buf_cmp_start++;
}
// No need to skip leading spaces or zeros here.
buf_cmp_len = strlen(buf_cmp_start);
/**
* If the sign is different, or
* some of the digits are different, or
* there is another digit present in the original string
* then we have NOT successfully parsed the value.
*/
if (orig_has_neg != recheck_has_neg ||
strncmp(buf_sig_digits, buf_cmp_start, strlen(buf_cmp_start)) != 0 ||
((int)strlen(buf_sig_digits) != buf_cmp_len &&
isdigit((int)buf_sig_digits[buf_cmp_len])
)
)
{
saved_errno = ERANGE;
}
}
// Not all sscanf impl's set the value properly when out of range.
// Always do this, even for properly functioning implementations,
// since it shouldn't slow things down much.
if (saved_errno == ERANGE)
{
if (orig_has_neg)
num64 = INT64_MIN;
else
num64 = INT64_MAX;
}
*retval = num64;
return 0;
} }
#ifndef HAVE_REALLOC #ifndef HAVE_REALLOC