clang/test/Analysis/errno-stdlibraryfunctions.c

   1 // RUN: %clang_analyze_cc1 -verify %s \
   2 // RUN:   -analyzer-checker=core \
   3 // RUN:   -analyzer-checker=debug.ExprInspection \
   4 // RUN:   -analyzer-checker=alpha.unix.StdCLibraryFunctions \
   5 // RUN:   -analyzer-checker=apiModeling.Errno \
   6 // RUN:   -analyzer-checker=alpha.unix.Errno \
   7 // RUN:   -analyzer-config alpha.unix.StdCLibraryFunctions:ModelPOSIX=true
   8
   9 #include "Inputs/errno_var.h"
  10
  11 typedef typeof(sizeof(int)) size_t;
  12 typedef __typeof(sizeof(int)) off_t;
  13 typedef size_t ssize_t;
  14 ssize_t send(int sockfd, const void *buf, size_t len, int flags);
  15 off_t lseek(int fildes, off_t offset, int whence);
  16
  17 void clang_analyzer_warnIfReached();
  18 void clang_analyzer_eval(int);
  19
  20 int unsafe_errno_read(int sock, void *data, int data_size) {
  21   if (send(sock, data, data_size, 0) != data_size) {
  22     if (errno == 1) {
  23       // expected-warning@-1{{An undefined value may be read from 'errno'}}
  24       return 0;
  25     }
  26   }
  27   return 1;
  28 }
  29
  30 int errno_lseek(int fildes, off_t offset) {
  31   off_t result = lseek(fildes, offset, 0);
  32   if (result == (off_t)-1) {
  33     // Failure path.
  34     // check if the function is modeled
  35     clang_analyzer_eval(errno != 0); // expected-warning{{TRUE}}
  36     return 2;
  37   }
  38   if (result != offset) {
  39     // Not success path (?)
  40     // not sure if this is a valid case, allow to check 'errno'
  41     if (errno == 1) { // no warning
  42       return 1;
  43     }
  44     clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
  45   }
  46   if (result == offset) {
  47     // The checker does not differentiate for this case.
  48     // In general case no relation exists between the arg 2 and the returned
  49     // value, only for SEEK_SET.
  50     if (errno == 1) { // no warning
  51       return 1;
  52     }
  53     clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
  54   }
  55   return 0;
  56 }