xref: /llvm-project/clang/test/Sema/format-strings.c (revision 5dd15a3c45c650fbe99b32dffa305b72f322d6c1)
1 // RUN: clang -fsyntax-only -verify %s
2 
3 // Define this to get vasprintf on Linux
4 #define _GNU_SOURCE
5 
6 #include <stdio.h>
7 #include <stdarg.h>
8 
9 char * global_fmt;
10 
11 void check_string_literal( FILE* fp, const char* s, char *buf, ... ) {
12 
13   char * b;
14   va_list ap;
15   va_start(ap,buf);
16 
17   printf(s); // expected-warning {{format string is not a string literal}}
18   vprintf(s,ap); // // no-warning
19   fprintf(fp,s); // expected-warning {{format string is not a string literal}}
20   vfprintf(fp,s,ap); // no-warning
21   asprintf(&b,s); // expected-warning {{format string is not a string lit}}
22   vasprintf(&b,s,ap); // no-warning
23   sprintf(buf,s); // expected-warning {{format string is not a string literal}}
24   snprintf(buf,2,s); // expected-warning {{format string is not a string lit}}
25   vsprintf(buf,s,ap); // no-warning
26   vsnprintf(buf,2,s,ap); // no-warning
27   vsnprintf(buf,2,global_fmt,ap); // expected-warning {{format string is not a string literal}}
28 }
29 
30 void check_writeback_specifier()
31 {
32   int x;
33   char *b;
34 
35   printf("%n",&x); // expected-warning {{'%n' in format string discouraged}}
36   sprintf(b,"%d%%%n",1, &x); // expected-warning {{'%n' in format string dis}}
37 }
38 
39 void check_invalid_specifier(FILE* fp, char *buf)
40 {
41   printf("%s%lb%d","unix",10,20); // expected-warning {{lid conversion '%lb'}}
42   fprintf(fp,"%%%l"); // expected-warning {{lid conversion '%l'}}
43   sprintf(buf,"%%%%%ld%d%d", 1, 2, 3); // no-warning
44   snprintf(buf, 2, "%%%%%ld%;%d", 1, 2, 3); // expected-warning {{sion '%;'}}
45 }
46 
47 void check_null_char_string(char* b)
48 {
49   printf("\0this is bogus%d",1); // expected-warning {{string contains '\0'}}
50   snprintf(b,10,"%%%%%d\0%d",1,2); // expected-warning {{string contains '\0'}}
51   printf("%\0d",1); // expected-warning {{string contains '\0'}}
52 }
53 
54 void check_empty_format_string(char* buf, ...)
55 {
56   va_list ap;
57   va_start(ap,buf);
58   vprintf("",ap); // expected-warning {{format string is empty}}
59   sprintf(buf,""); // expected-warning {{format string is empty}}
60 }
61 
62 void check_wide_string(char* b, ...)
63 {
64   va_list ap;
65   va_start(ap,b);
66 
67   printf(L"foo %d",2); // expected-warning {{incompatible pointer types}}, expected-warning {{should not be a wide string}}
68   vasprintf(&b,L"bar %d",ap); // expected-warning {{incompatible pointer types}}, expected-warning {{should not be a wide string}}
69 }
70 
71 void check_asterisk_precision_width(int x) {
72   printf("%*d"); // expected-warning {{'*' specified field width is missing a matching 'int' argument}}
73   printf("%.*d"); // expected-warning {{'.*' specified field precision is missing a matching 'int' argument}}
74   printf("%*d",12,x); // no-warning
75   printf("%*d","foo",x); // expected-warning {{field width should have type 'int', but argument has type 'char *'}}
76   printf("%.*d","foo",x); // expected-warning {{field precision should have type 'int', but argument has type 'char *'}}
77 }
78