90 lines · c
1// RUN: %clang_analyze_cc1 -verify %s \2// RUN: -analyzer-checker=core,unix.StdCLibraryFunctions \3// RUN: -analyzer-config unix.StdCLibraryFunctions:ModelPOSIX=true \4// RUN: -analyzer-output=text5 6#include "Inputs/std-c-library-functions-POSIX.h"7#define NULL ((void *)0)8 9char *getenv(const char *);10int isalpha(int);11int isdigit(int);12int islower(int);13 14char test_getenv() {15 char *env = getenv("VAR"); // \16 // expected-note{{Assuming the environment variable does not exist}} \17 // expected-note{{'env' initialized here}}18 19 return env[0]; // \20 // expected-warning{{Array access (from variable 'env') results in a null pointer dereference}} \21 // expected-note {{Array access (from variable 'env') results in a null pointer dereference}}22}23 24int test_isalpha(int *x, char c, char d) {25 int iad = isalpha(d);26 if (isalpha(c)) {// \27 // expected-note{{Taking true branch}}28 x = NULL; // \29 // expected-note{{Null pointer value stored to 'x'}}30 }31 32 return *x; // \33 // expected-warning{{Dereference of null pointer (loaded from variable 'x')}} \34 // expected-note {{Dereference of null pointer (loaded from variable 'x')}}35}36 37int test_isdigit(int *x, char c) {38 if (!isdigit(c)) {// \39 // expected-note{{Taking true branch}}40 x = NULL; // \41 // expected-note{{Null pointer value stored to 'x'}}42 }43 44 return *x; // \45 // expected-warning{{Dereference of null pointer (loaded from variable 'x')}} \46 // expected-note {{Dereference of null pointer (loaded from variable 'x')}}47}48 49int test_islower(int *x) {50 char c = 'c';51 // No "Assuming..." note. We aren't assuming anything. We *know*.52 if (islower(c)) { // \53 // expected-note{{Taking true branch}}54 x = NULL; // \55 // expected-note{{Null pointer value stored to 'x'}}56 }57 58 return *x; // \59 // expected-warning{{Dereference of null pointer (loaded from variable 'x')}} \60 // expected-note {{Dereference of null pointer (loaded from variable 'x')}}61}62 63int test_bugpath_notes(FILE *f1, char c, FILE *f2) {64 // This test has the purpose of checking that notes appear at correct place.65 long a = ftell(f2); // no note66 if (a == -1) // \67 // expected-note{{Taking false branch}}68 return -1;69 int l = islower(c); // no note70 a = ftell(f1); // \71 // expected-note{{Value assigned to 'a'}} \72 // expected-note{{Assuming that 'ftell' fails}}73 return dup(a); // \74 // expected-warning{{The 1st argument to 'dup' is -1 but should be >= 0}} \75 // expected-note{{The 1st argument to 'dup' is -1 but should be >= 0}}76}77 78int test_fileno_arg_note(FILE *f1) {79 return dup(fileno(f1)); // no warning80}81 82int test_readlink_bufsize_zero(char *Buf, size_t Bufsize) {83 ssize_t Ret = readlink("path", Buf, Bufsize); // \84 // expected-note{{Assuming that argument 'bufsize' is 0}} \85 // expected-note{{'Ret' initialized here}}86 return 1 / Ret; // \87 // expected-warning{{Division by zero}} \88 // expected-note{{Division by zero}}89}90