gcc/testsuite/c-c++-common/analyzer/fd-2.c

   1 int open(const char *, int mode);
   2 void close(int fd);
   3 #define O_RDONLY 0
   4 #define O_WRONLY 1
   5 #define O_RDWR 2
   6 #define STDIN 0
   7
   8 typedef enum {
   9   S_IRWXU
  10   // etc
  11 } mode_t;
  12
  13 int creat (const char *, mode_t mode);
  14
  15 void
  16 test_1 (const char *path)
  17 {
  18     int fd = open (path, O_RDWR); /* { dg-message "\\(1\\) opened here" } */
  19     close (fd); /* { dg-message "\\(2\\) first 'close' here" "event1" } */
  20     close (fd); /* { dg-warning "double 'close' of file descriptor 'fd' \\\[CWE-1341\\\]" "warning" } */
  21     /* { dg-message "\\(3\\) second 'close' here; first 'close' was at \\(2\\)" "event2" { target *-*-* } .-1 } */
  22 }
  23
  24 void
  25 test_2 (const char *path)
  26 {
  27     int fd = open (path, O_RDWR); /* { dg-message "\\(1\\) opened here" } */
  28     if (fd < 0) /* { dg-message "\\(2\\) assuming 'fd' is a valid file descriptor \\(>= 0\\)" "event1" } */
  29     /* { dg-message "\\(3\\) following 'false' branch \\(when 'fd >= 0'\\)..." "event2" { target *-*-* } .-1 } */
  30         return;
  31     close (fd); /* { dg-message "\\(4\\) ...to here" "event1" } */
  32     /* { dg-message "\\(5\\) first 'close' here" "event2" { target *-*-* } .-1 } */
  33     close (fd); /* { dg-warning "double 'close' of file descriptor 'fd' \\\[CWE-1341\\\]" "warning" } */
  34     /* {dg-message "\\(6\\) second 'close' here; first was at \\(5\\)" "" { target *-*-* } .-1 } */
  35 }
  36
  37 void
  38 test_3 ()
  39 {
  40     /* FD 0 is stdin at the entry to "main" and thus read-only, but we have no
  41     guarantees here that it hasn't been closed and then reopened for
  42     writing, so we can't issue a warning */
  43
  44     int fd = STDIN;
  45     close(fd); /* { dg-message "\\(1\\) first 'close' here" } */
  46     close(fd); /* { dg-warning "double 'close' of file descriptor 'fd' \\\[CWE-1341\\\]" "warning" } */
  47      /* { dg-message "\\(2\\) second 'close' here; first 'close' was at \\(1\\)" "event2" { target *-*-* } .-1 } */
  48 }
  49
  50 void
  51 test_4 ()
  52 {
  53     int fd = -1;
  54     close(fd);
  55     close(fd);
  56 }
  57
  58 void
  59 test_5 (const char *path, mode_t mode)
  60 {
  61     int fd = creat (path, mode);
  62     close(fd);
  63     close(fd); /* { dg-warning "double 'close' of file descriptor 'fd' \\\[CWE-1341\\\]" "warning" } */
  64 }