1 // RUN: %clang_analyze_cc1 -analyzer-checker=core \
2 // RUN: -analyzer-checker=unix.Stream \
3 // RUN: -analyzer-config unix.Stream:Pedantic=true \
4 // RUN: -analyzer-checker=unix.Errno \
5 // RUN: -analyzer-checker=unix.StdCLibraryFunctions \
6 // RUN: -analyzer-config unix.StdCLibraryFunctions:ModelPOSIX=true \
7 // RUN: -analyzer-output text -verify %s
8
9 #include "Inputs/system-header-simulator.h"
10 #include "Inputs/errno_func.h"
11
check_fopen(void)12 void check_fopen(void) {
13 FILE *F = fopen("xxx", "r");
14 // expected-note@-1{{Assuming that 'fopen' is successful; 'errno' becomes undefined after the call}}
15 // expected-note@+2{{'F' is non-null}}
16 // expected-note@+1{{Taking false branch}}
17 if (!F)
18 return;
19 if (errno) {} // expected-warning{{An undefined value may be read from 'errno' [unix.Errno]}}
20 // expected-note@-1{{An undefined value may be read from 'errno'}}
21 fclose(F);
22 }
23
check_tmpfile(void)24 void check_tmpfile(void) {
25 FILE *F = tmpfile();
26 // expected-note@-1{{Assuming that 'tmpfile' is successful; 'errno' becomes undefined after the call}}
27 // expected-note@+2{{'F' is non-null}}
28 // expected-note@+1{{Taking false branch}}
29 if (!F)
30 return;
31 if (errno) {} // expected-warning{{An undefined value may be read from 'errno' [unix.Errno]}}
32 // expected-note@-1{{An undefined value may be read from 'errno'}}
33 fclose(F);
34 }
35
check_freopen(void)36 void check_freopen(void) {
37 FILE *F = tmpfile();
38 // expected-note@+2{{'F' is non-null}}
39 // expected-note@+1{{Taking false branch}}
40 if (!F)
41 return;
42 F = freopen("xxx", "w", F);
43 // expected-note@-1{{Assuming that 'freopen' is successful; 'errno' becomes undefined after the call}}
44 // expected-note@+2{{'F' is non-null}}
45 // expected-note@+1{{Taking false branch}}
46 if (!F)
47 return;
48 if (errno) {} // expected-warning{{An undefined value may be read from 'errno'}}
49 // expected-note@-1{{An undefined value may be read from 'errno'}}
50 fclose(F);
51 }
52
check_fclose(void)53 void check_fclose(void) {
54 FILE *F = tmpfile();
55 // expected-note@+2{{'F' is non-null}}
56 // expected-note@+1{{Taking false branch}}
57 if (!F)
58 return;
59 (void)fclose(F);
60 // expected-note@-1{{Assuming that 'fclose' is successful; 'errno' becomes undefined after the call}}
61 if (errno) {} // expected-warning{{An undefined value may be read from 'errno'}}
62 // expected-note@-1{{An undefined value may be read from 'errno'}}
63 }
64
check_fread(void)65 void check_fread(void) {
66 char Buf[10];
67 FILE *F = tmpfile();
68 // expected-note@+2{{'F' is non-null}}
69 // expected-note@+1{{Taking false branch}}
70 if (!F)
71 return;
72 (void)fread(Buf, 1, 10, F);
73 // expected-note@-1{{Assuming that 'fread' is successful; 'errno' becomes undefined after the call}}
74 if (errno) {} // expected-warning{{An undefined value may be read from 'errno'}}
75 // expected-note@-1{{An undefined value may be read from 'errno'}}
76 (void)fclose(F);
77 }
78
check_fread_size0(void)79 void check_fread_size0(void) {
80 char Buf[10];
81 FILE *F = tmpfile();
82 // expected-note@+2{{'F' is non-null}}
83 // expected-note@+1{{Taking false branch}}
84 if (!F)
85 return;
86 fread(Buf, 0, 1, F);
87 // expected-note@-1{{Assuming that argument 'size' to 'fread' is 0; 'errno' becomes undefined after the call}}
88 if (errno) {} // expected-warning{{An undefined value may be read from 'errno'}}
89 // expected-note@-1{{An undefined value may be read from 'errno'}}
90 }
91
check_fread_nmemb0(void)92 void check_fread_nmemb0(void) {
93 char Buf[10];
94 FILE *F = tmpfile();
95 // expected-note@+2{{'F' is non-null}}
96 // expected-note@+1{{Taking false branch}}
97 if (!F)
98 return;
99 fread(Buf, 1, 0, F);
100 // expected-note@-1{{Assuming that 'fread' is successful; 'errno' becomes undefined after the call}}
101 if (errno) {} // expected-warning{{An undefined value may be read from 'errno'}}
102 // expected-note@-1{{An undefined value may be read from 'errno'}}
103 }
104
check_fwrite(void)105 void check_fwrite(void) {
106 char Buf[] = "0123456789";
107 FILE *F = tmpfile();
108 // expected-note@+2{{'F' is non-null}}
109 // expected-note@+1{{Taking false branch}}
110 if (!F)
111 return;
112 int R = fwrite(Buf, 1, 10, F);
113 // expected-note@-1{{Assuming that 'fwrite' is successful; 'errno' becomes undefined after the call}}
114 if (errno) {} // expected-warning{{An undefined value may be read from 'errno'}}
115 // expected-note@-1{{An undefined value may be read from 'errno'}}
116 (void)fclose(F);
117 }
118
check_fseek(void)119 void check_fseek(void) {
120 FILE *F = tmpfile();
121 // expected-note@+2{{'F' is non-null}}
122 // expected-note@+1{{Taking false branch}}
123 if (!F)
124 return;
125 (void)fseek(F, 11, SEEK_SET);
126 // expected-note@-1{{Assuming that 'fseek' is successful; 'errno' becomes undefined after the call}}
127 if (errno) {} // expected-warning{{An undefined value may be read from 'errno'}}
128 // expected-note@-1{{An undefined value may be read from 'errno'}}
129 (void)fclose(F);
130 }
131
check_rewind_errnocheck(void)132 void check_rewind_errnocheck(void) {
133 FILE *F = tmpfile();
134 // expected-note@+2{{'F' is non-null}}
135 // expected-note@+1{{Taking false branch}}
136 if (!F)
137 return;
138 errno = 0;
139 rewind(F); // expected-note{{After calling 'rewind' reading 'errno' is required to find out if the call has failed}}
140 fclose(F); // expected-warning{{Value of 'errno' was not checked and may be overwritten by function 'fclose' [unix.Errno]}}
141 // expected-note@-1{{Value of 'errno' was not checked and may be overwritten by function 'fclose'}}
142 }
143
check_fileno(void)144 void check_fileno(void) {
145 // nothing to check: checker assumes that 'fileno' is always successful
146 // (and does not change 'errno')
147 }
148
check_fwrite_zeroarg(size_t Siz)149 void check_fwrite_zeroarg(size_t Siz) {
150 char Buf[] = "0123456789";
151 FILE *F = tmpfile();
152 // expected-note@+2{{'F' is non-null}}
153 // expected-note@+1{{Taking false branch}}
154 if (!F)
155 return;
156 errno = 0;
157 int R = fwrite(Buf, Siz, 1, F);
158 // expected-note@-1{{Assuming that argument 'size' to 'fwrite' is 0; 'errno' becomes undefined after the call}}
159 // expected-note@+2{{'R' is <= 0}}
160 // expected-note@+1{{Taking true branch}}
161 if (R <= 0) {
162 if (errno) {} // expected-warning{{An undefined value may be read from 'errno'}}
163 // expected-note@-1{{An undefined value may be read from 'errno'}}
164 }
165 (void)fclose(F);
166 }
167