diff options
Diffstat (limited to 'src/common/util.c')
-rw-r--r-- | src/common/util.c | 192 |
1 files changed, 152 insertions, 40 deletions
diff --git a/src/common/util.c b/src/common/util.c index a0dff2e35b..ce67252852 100644 --- a/src/common/util.c +++ b/src/common/util.c @@ -290,37 +290,6 @@ _tor_free(void *mem) tor_free(mem); } -#if defined(HAVE_MALLOC_GOOD_SIZE) && !defined(HAVE_MALLOC_GOOD_SIZE_PROTOTYPE) -/* Some version of Mac OSX have malloc_good_size in their libc, but not - * actually defined in malloc/malloc.h. We detect this and work around it by - * prototyping. - */ -extern size_t malloc_good_size(size_t size); -#endif - -/** Allocate and return a chunk of memory of size at least *<b>size</b>, using - * the same resources we would use to malloc *<b>sizep</b>. Set *<b>sizep</b> - * to the number of usable bytes in the chunk of memory. */ -void * -_tor_malloc_roundup(size_t *sizep DMALLOC_PARAMS) -{ -#ifdef HAVE_MALLOC_GOOD_SIZE - tor_assert(*sizep < SIZE_T_CEILING); - *sizep = malloc_good_size(*sizep); - return _tor_malloc(*sizep DMALLOC_FN_ARGS); -#elif 0 && defined(HAVE_MALLOC_USABLE_SIZE) && !defined(USE_DMALLOC) - /* Never use malloc_usable_size(); it makes valgrind really unhappy, - * and doesn't win much in terms of usable space where it exists. */ - void *result; - tor_assert(*sizep < SIZE_T_CEILING); - result = _tor_malloc(*sizep DMALLOC_FN_ARGS); - *sizep = malloc_usable_size(result); - return result; -#else - return _tor_malloc(*sizep DMALLOC_FN_ARGS); -#endif -} - /** Call the platform malloc info function, and dump the results to the log at * level <b>severity</b>. If no such function exists, do nothing. */ void @@ -655,6 +624,16 @@ fast_memcmpstart(const void *mem, size_t memlen, return fast_memcmp(mem, prefix, plen); } +/** Given a nul-terminated string s, set every character before the nul + * to zero. */ +void +tor_strclear(char *s) +{ + while (*s) { + *s++ = '\0'; + } +} + /** Return a pointer to the first char of s that is not whitespace and * not a comment, or to the terminating NUL if no such character exists. */ @@ -2684,9 +2663,9 @@ digit_to_num(char d) * success, store the result in <b>out</b>, advance bufp to the next * character, and return 0. On failure, return -1. */ static int -scan_unsigned(const char **bufp, unsigned *out, int width, int base) +scan_unsigned(const char **bufp, unsigned long *out, int width, int base) { - unsigned result = 0; + unsigned long result = 0; int scanned_so_far = 0; const int hex = base==16; tor_assert(base == 10 || base == 16); @@ -2698,8 +2677,8 @@ scan_unsigned(const char **bufp, unsigned *out, int width, int base) while (**bufp && (hex?TOR_ISXDIGIT(**bufp):TOR_ISDIGIT(**bufp)) && scanned_so_far < width) { int digit = hex?hex_decode_digit(*(*bufp)++):digit_to_num(*(*bufp)++); - unsigned new_result = result * base + digit; - if (new_result > UINT32_MAX || new_result < result) + unsigned long new_result = result * base + digit; + if (new_result < result) return -1; /* over/underflow. */ result = new_result; ++scanned_so_far; @@ -2712,6 +2691,89 @@ scan_unsigned(const char **bufp, unsigned *out, int width, int base) return 0; } +/** Helper: Read an signed int from *<b>bufp</b> of up to <b>width</b> + * characters. (Handle arbitrary width if <b>width</b> is less than 0.) On + * success, store the result in <b>out</b>, advance bufp to the next + * character, and return 0. On failure, return -1. */ +static int +scan_signed(const char **bufp, long *out, int width) +{ + int neg = 0; + unsigned long result = 0; + + if (!bufp || !*bufp || !out) + return -1; + if (width<0) + width=MAX_SCANF_WIDTH; + + if (**bufp == '-') { + neg = 1; + ++*bufp; + --width; + } + + if (scan_unsigned(bufp, &result, width, 10) < 0) + return -1; + + if (neg) { + if (result > ((unsigned long)LONG_MAX) + 1) + return -1; /* Underflow */ + *out = -(long)result; + } else { + if (result > LONG_MAX) + return -1; /* Overflow */ + *out = (long)result; + } + + return 0; +} + +/** Helper: Read a decimal-formatted double from *<b>bufp</b> of up to + * <b>width</b> characters. (Handle arbitrary width if <b>width</b> is less + * than 0.) On success, store the result in <b>out</b>, advance bufp to the + * next character, and return 0. On failure, return -1. */ +static int +scan_double(const char **bufp, double *out, int width) +{ + int neg = 0; + double result = 0; + int scanned_so_far = 0; + + if (!bufp || !*bufp || !out) + return -1; + if (width<0) + width=MAX_SCANF_WIDTH; + + if (**bufp == '-') { + neg = 1; + ++*bufp; + } + + while (**bufp && TOR_ISDIGIT(**bufp) && scanned_so_far < width) { + const int digit = digit_to_num(*(*bufp)++); + result = result * 10 + digit; + ++scanned_so_far; + } + if (**bufp == '.') { + double fracval = 0, denominator = 1; + ++*bufp; + ++scanned_so_far; + while (**bufp && TOR_ISDIGIT(**bufp) && scanned_so_far < width) { + const int digit = digit_to_num(*(*bufp)++); + fracval = fracval * 10 + digit; + denominator *= 10; + ++scanned_so_far; + } + result += fracval / denominator; + } + + if (!scanned_so_far) /* No actual digits scanned */ + return -1; + + *out = neg ? -result : result; + return 0; +} + /** Helper: copy up to <b>width</b> non-space characters from <b>bufp</b> to * <b>out</b>. Make sure <b>out</b> is nul-terminated. Advance <b>bufp</b> * to the next non-space character or the EOS. */ @@ -2748,6 +2810,7 @@ tor_vsscanf(const char *buf, const char *pattern, va_list ap) } } else { int width = -1; + int longmod = 0; ++pattern; if (TOR_ISDIGIT(*pattern)) { width = digit_to_num(*pattern++); @@ -2760,17 +2823,57 @@ tor_vsscanf(const char *buf, const char *pattern, va_list ap) if (!width) /* No zero-width things. */ return -1; } + if (*pattern == 'l') { + longmod = 1; + ++pattern; + } if (*pattern == 'u' || *pattern == 'x') { - unsigned *u = va_arg(ap, unsigned *); + unsigned long u; const int base = (*pattern == 'u') ? 10 : 16; if (!*buf) return n_matched; - if (scan_unsigned(&buf, u, width, base)<0) + if (scan_unsigned(&buf, &u, width, base)<0) return n_matched; + if (longmod) { + unsigned long *out = va_arg(ap, unsigned long *); + *out = u; + } else { + unsigned *out = va_arg(ap, unsigned *); + if (u > UINT_MAX) + return n_matched; + *out = (unsigned) u; + } + ++pattern; + ++n_matched; + } else if (*pattern == 'f') { + double *d = va_arg(ap, double *); + if (!longmod) + return -1; /* float not supported */ + if (!*buf) + return n_matched; + if (scan_double(&buf, d, width)<0) + return n_matched; + ++pattern; + ++n_matched; + } else if (*pattern == 'd') { + long lng=0; + if (scan_signed(&buf, &lng, width)<0) + return n_matched; + if (longmod) { + long *out = va_arg(ap, long *); + *out = lng; + } else { + int *out = va_arg(ap, int *); + if (lng < INT_MIN || lng > INT_MAX) + return n_matched; + *out = (int)lng; + } ++pattern; ++n_matched; } else if (*pattern == 's') { char *s = va_arg(ap, char *); + if (longmod) + return -1; if (width < 0) return -1; if (scan_string(&buf, s, width)<0) @@ -2779,6 +2882,8 @@ tor_vsscanf(const char *buf, const char *pattern, va_list ap) ++n_matched; } else if (*pattern == 'c') { char *ch = va_arg(ap, char *); + if (longmod) + return -1; if (width != -1) return -1; if (!*buf) @@ -2789,6 +2894,8 @@ tor_vsscanf(const char *buf, const char *pattern, va_list ap) } else if (*pattern == '%') { if (*buf != '%') return n_matched; + if (longmod) + return -1; ++buf; ++pattern; } else { @@ -2802,9 +2909,14 @@ tor_vsscanf(const char *buf, const char *pattern, va_list ap) /** Minimal sscanf replacement: parse <b>buf</b> according to <b>pattern</b> * and store the results in the corresponding argument fields. Differs from - * sscanf in that it: Only handles %u, %x, %c and %Ns. Does not handle - * arbitrarily long widths. %u and %x do not consume any space. Is - * locale-independent. Returns -1 on malformed patterns. + * sscanf in that: + * <ul><li>It only handles %u, %lu, %x, %lx, %<NUM>s, %d, %ld, %lf, and %c. + * <li>It only handles decimal inputs for %lf. (12.3, not 1.23e1) + * <li>It does not handle arbitrarily long widths. + * <li>Numbers do not consume any space characters. + * <li>It is locale-independent. + * <li>%u and %x do not consume any space. + * <li>It returns -1 on malformed patterns.</ul> * * (As with other locale-independent functions, we need this to parse data that * is in ASCII without worrying that the C library's locale-handling will make |