tools/testing/selftests/bpf/progs/btf_dump_test_case_syntax.c

   1 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
   2
   3 /*
   4  * BTF-to-C dumper test for majority of C syntax quirks.
   5  *
   6  * Copyright (c) 2019 Facebook
   7  */
   8 /* ----- START-EXPECTED-OUTPUT ----- */
   9 enum e1 {
  10         A = 0,
  11         B = 1,
  12 };
  13
  14 enum e2 {
  15         C = 100,
  16         D = -100,
  17         E = 0,
  18 };
  19
  20 typedef enum e2 e2_t;
  21
  22 typedef enum {
  23         F = 0,
  24         G = 1,
  25         H = 2,
  26 } e3_t;
  27
  28 typedef int int_t;
  29
  30 typedef volatile const int * volatile const crazy_ptr_t;
  31
  32 typedef int *****we_need_to_go_deeper_ptr_t;
  33
  34 typedef volatile const we_need_to_go_deeper_ptr_t * restrict * volatile * const * restrict volatile * restrict const * volatile const * restrict volatile const how_about_this_ptr_t;
  35
  36 typedef int *ptr_arr_t[10];
  37
  38 typedef void (*fn_ptr1_t)(int);
  39
  40 typedef void (*printf_fn_t)(const char *, ...);
  41
  42 /* ------ END-EXPECTED-OUTPUT ------ */
  43 /*
  44  * While previous function pointers are pretty trivial (C-syntax-level
  45  * trivial), the following are deciphered here for future generations:
  46  *
  47  * - `fn_ptr2_t`: function, taking anonymous struct as a first arg and pointer
  48  *   to a function, that takes int and returns int, as a second arg; returning
  49  *   a pointer to a const pointer to a char. Equivalent to:
  50  *      typedef struct { int a; } s_t;
  51  *      typedef int (*fn_t)(int);
  52  *      typedef char * const * (*fn_ptr2_t)(s_t, fn_t);
  53  *
  54  * - `fn_complext_t`: pointer to a function returning struct and accepting
  55  *   union and struct. All structs and enum are anonymous and defined inline.
  56  *
  57  * - `signal_t: pointer to a function accepting a pointer to a function as an
  58  *   argument and returning pointer to a function as a result. Sane equivalent:
  59  *      typedef void (*signal_handler_t)(int);
  60  *      typedef signal_handler_t (*signal_ptr_t)(int, signal_handler_t);
  61  *
  62  * - fn_ptr_arr1_t: array of pointers to a function accepting pointer to
  63  *   a pointer to an int and returning pointer to a char. Easy.
  64  *
  65  * - fn_ptr_arr2_t: array of const pointers to a function taking no arguments
  66  *   and returning a const pointer to a function, that takes pointer to a
  67  *   `int -> char *` function and returns pointer to a char. Equivalent:
  68  *   typedef char * (*fn_input_t)(int);
  69  *   typedef char * (*fn_output_outer_t)(fn_input_t);
  70  *   typedef const fn_output_outer_t (* fn_output_inner_t)();
  71  *   typedef const fn_output_inner_t fn_ptr_arr2_t[5];
  72  */
  73 /* ----- START-EXPECTED-OUTPUT ----- */
  74 typedef char * const * (*fn_ptr2_t)(struct {
  75         int a;
  76 }, int (*)(int));
  77
  78 typedef struct {
  79         int a;
  80         void (*b)(int, struct {
  81                 int c;
  82         }, union {
  83                 char d;
  84                 int e[5];
  85         });
  86 } (*fn_complex_t)(union {
  87         void *f;
  88         char g[16];
  89 }, struct {
  90         int h;
  91 });
  92
  93 typedef void (* (*signal_t)(int, void (*)(int)))(int);
  94
  95 typedef char * (*fn_ptr_arr1_t[10])(int **);
  96
  97 typedef char * (* const (* const fn_ptr_arr2_t[5])())(char * (*)(int));
  98
  99 struct struct_w_typedefs {
 100         int_t a;
 101         crazy_ptr_t b;
 102         we_need_to_go_deeper_ptr_t c;
 103         how_about_this_ptr_t d;
 104         ptr_arr_t e;
 105         fn_ptr1_t f;
 106         printf_fn_t g;
 107         fn_ptr2_t h;
 108         fn_complex_t i;
 109         signal_t j;
 110         fn_ptr_arr1_t k;
 111         fn_ptr_arr2_t l;
 112 };
 113
 114 typedef struct {
 115         int x;
 116         int y;
 117         int z;
 118 } anon_struct_t;
 119
 120 struct struct_fwd;
 121
 122 typedef struct struct_fwd struct_fwd_t;
 123
 124 typedef struct struct_fwd *struct_fwd_ptr_t;
 125
 126 union union_fwd;
 127
 128 typedef union union_fwd union_fwd_t;
 129
 130 typedef union union_fwd *union_fwd_ptr_t;
 131
 132 struct struct_empty {};
 133
 134 struct struct_simple {
 135         int a;
 136         char b;
 137         const int_t *p;
 138         struct struct_empty s;
 139         enum e2 e;
 140         enum {
 141                 ANON_VAL1 = 1,
 142                 ANON_VAL2 = 2,
 143         } f;
 144         int arr1[13];
 145         enum e2 arr2[5];
 146 };
 147
 148 union union_empty {};
 149
 150 union union_simple {
 151         void *ptr;
 152         int num;
 153         int_t num2;
 154         union union_empty u;
 155 };
 156
 157 struct struct_in_struct {
 158         struct struct_simple simple;
 159         union union_simple also_simple;
 160         struct {
 161                 int a;
 162         } not_so_hard_as_well;
 163         union {
 164                 int b;
 165                 int c;
 166         } anon_union_is_good;
 167         struct {
 168                 int d;
 169                 int e;
 170         };
 171         union {
 172                 int f;
 173                 int g;
 174         };
 175 };
 176
 177 struct struct_with_embedded_stuff {
 178         int a;
 179         struct {
 180                 int b;
 181                 struct {
 182                         struct struct_with_embedded_stuff *c;
 183                         const char *d;
 184                 } e;
 185                 union {
 186                         volatile long int f;
 187                         void * restrict g;
 188                 };
 189         };
 190         union {
 191                 const int_t *h;
 192                 void (*i)(char, int, void *);
 193         } j;
 194         enum {
 195                 K = 100,
 196                 L = 200,
 197         } m;
 198         char n[16];
 199         struct {
 200                 char o;
 201                 int p;
 202                 void (*q)(int);
 203         } r[5];
 204         struct struct_in_struct s[10];
 205         int t[11];
 206 };
 207
 208 struct root_struct {
 209         enum e1 _1;
 210         enum e2 _2;
 211         e2_t _2_1;
 212         e3_t _2_2;
 213         struct struct_w_typedefs _3;
 214         anon_struct_t _7;
 215         struct struct_fwd *_8;
 216         struct_fwd_t *_9;
 217         struct_fwd_ptr_t _10;
 218         union union_fwd *_11;
 219         union_fwd_t *_12;
 220         union_fwd_ptr_t _13;
 221         struct struct_with_embedded_stuff _14;
 222 };
 223
 224 /* ------ END-EXPECTED-OUTPUT ------ */
 225
 226 int f(struct root_struct *s)
 227 {
 228         return 0;
 229 }