sanitizer_libc.cc revision 8cd0df78c317106be477c5496f481af0563a5208 
1//===-- sanitizer_libc.cc -------------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file is shared between AddressSanitizer and ThreadSanitizer
11// run-time libraries. See sanitizer_libc.h for details.
12//===----------------------------------------------------------------------===//
13#include "sanitizer_common.h"
14#include "sanitizer_libc.h"
15
16namespace __sanitizer {
17
18s64 internal_atoll(const char *nptr) {
19  return internal_simple_strtoll(nptr, (char**)0, 10);
20}
21
22void *internal_memchr(const void *s, int c, uptr n) {
23  const char* t = (char*)s;
24  for (uptr i = 0; i < n; ++i, ++t)
25    if (*t == c)
26      return (void*)t;
27  return 0;
28}
29
30int internal_memcmp(const void* s1, const void* s2, uptr n) {
31  const char* t1 = (char*)s1;
32  const char* t2 = (char*)s2;
33  for (uptr i = 0; i < n; ++i, ++t1, ++t2)
34    if (*t1 != *t2)
35      return *t1 < *t2 ? -1 : 1;
36  return 0;
37}
38
39void *internal_memcpy(void *dest, const void *src, uptr n) {
40  char *d = (char*)dest;
41  char *s = (char*)src;
42  for (uptr i = 0; i < n; ++i)
43    d[i] = s[i];
44  return dest;
45}
46
47void *internal_memset(void* s, int c, uptr n) {
48  // The next line prevents Clang from making a call to memset() instead of the
49  // loop below.
50  // FIXME: building the runtime with -ffreestanding is a better idea. However
51  // there currently are linktime problems due to PR12396.
52  char volatile *t = (char*)s;
53  for (uptr i = 0; i < n; ++i, ++t) {
54    *t = c;
55  }
56  return s;
57}
58
59char* internal_strdup(const char *s) {
60  uptr len = internal_strlen(s);
61  char *s2 = (char*)InternalAlloc(len + 1);
62  internal_memcpy(s2, s, len);
63  s2[len] = 0;
64  return s2;
65}
66
67int internal_strcmp(const char *s1, const char *s2) {
68  while (true) {
69    unsigned c1 = *s1;
70    unsigned c2 = *s2;
71    if (c1 != c2) return (c1 < c2) ? -1 : 1;
72    if (c1 == 0) break;
73    s1++;
74    s2++;
75  }
76  return 0;
77}
78
79int internal_strncmp(const char *s1, const char *s2, uptr n) {
80  for (uptr i = 0; i < n; i++) {
81    unsigned c1 = *s1;
82    unsigned c2 = *s2;
83    if (c1 != c2) return (c1 < c2) ? -1 : 1;
84    if (c1 == 0) break;
85    s1++;
86    s2++;
87  }
88  return 0;
89}
90
91char* internal_strchr(const char *s, int c) {
92  while (true) {
93    if (*s == (char)c)
94      return (char*)s;
95    if (*s == 0)
96      return 0;
97    s++;
98  }
99}
100
101char *internal_strrchr(const char *s, int c) {
102  const char *res = 0;
103  for (uptr i = 0; s[i]; i++) {
104    if (s[i] == c) res = s + i;
105  }
106  return (char*)res;
107}
108
109uptr internal_strlen(const char *s) {
110  uptr i = 0;
111  while (s[i]) i++;
112  return i;
113}
114
115char *internal_strncat(char *dst, const char *src, uptr n) {
116  uptr len = internal_strlen(dst);
117  uptr i;
118  for (i = 0; i < n && src[i]; i++)
119    dst[len + i] = src[i];
120  dst[len + i] = 0;
121  return dst;
122}
123
124char *internal_strncpy(char *dst, const char *src, uptr n) {
125  uptr i;
126  for (i = 0; i < n && src[i]; i++)
127    dst[i] = src[i];
128  for (; i < n; i++)
129    dst[i] = '\0';
130  return dst;
131}
132
133uptr internal_strnlen(const char *s, uptr maxlen) {
134  uptr i = 0;
135  while (i < maxlen && s[i]) i++;
136  return i;
137}
138
139char *internal_strstr(const char *haystack, const char *needle) {
140  // This is O(N^2), but we are not using it in hot places.
141  uptr len1 = internal_strlen(haystack);
142  uptr len2 = internal_strlen(needle);
143  if (len1 < len2) return 0;
144  for (uptr pos = 0; pos <= len1 - len2; pos++) {
145    if (internal_memcmp(haystack + pos, needle, len2) == 0)
146      return (char*)haystack + pos;
147  }
148  return 0;
149}
150
151s64 internal_simple_strtoll(const char *nptr, char **endptr, int base) {
152  CHECK(base == 10);
153  while (IsSpace(*nptr)) nptr++;
154  int sgn = 1;
155  u64 res = 0;
156  bool have_digits = false;
157  char *old_nptr = (char*)nptr;
158  if (*nptr == '+') {
159    sgn = 1;
160    nptr++;
161  } else if (*nptr == '-') {
162    sgn = -1;
163    nptr++;
164  }
165  while (IsDigit(*nptr)) {
166    res = (res <= UINT64_MAX / 10) ? res * 10 : UINT64_MAX;
167    int digit = ((*nptr) - '0');
168    res = (res <= UINT64_MAX - digit) ? res + digit : UINT64_MAX;
169    have_digits = true;
170    nptr++;
171  }
172  if (endptr != 0) {
173    *endptr = (have_digits) ? (char*)nptr : old_nptr;
174  }
175  if (sgn > 0) {
176    return (s64)(Min((u64)INT64_MAX, res));
177  } else {
178    return (res > INT64_MAX) ? INT64_MIN : ((s64)res * -1);
179  }
180}
181
182}  // namespace __sanitizer
183