chrome/test/data/nacl/nonsfi/libc_free.c

   1 /*
   2  * Copyright 2014 The Chromium Authors. All rights reserved.
   3  * Use of this source code is governed by a BSD-style license that can be
   4  * found in the LICENSE file.
   5  */
   6
   7 /*
   8  * This is a minimal NaCl program without libc. It uses NaCl's stable IRT ABI.
   9  */
  10
  11 #include <stdint.h>
  12
  13 #include "native_client/src/include/elf_auxv.h"
  14 #include "native_client/src/untrusted/irt/irt.h"
  15 #include "ppapi/nacl_irt/irt_ppapi.h"
  16 #include "ppapi/c/pp_errors.h"
  17 #include "ppapi/c/ppp_instance.h"
  18
  19 static struct nacl_irt_basic __libnacl_irt_basic;
  20 static struct nacl_irt_fdio __libnacl_irt_fdio;
  21 static TYPE_nacl_irt_query __nacl_irt_query;
  22 static struct PPP_Instance_1_0 ppp_instance;
  23
  24 /*
  25  * To support 64bit binary, we declare Elf_auxv_t by using uintptr_t.
  26  * See also native_client/src/include/elf32.h.
  27  */
  28 typedef struct {
  29   uintptr_t a_type;
  30   union {
  31     uintptr_t a_val;
  32   } a_un;
  33 } Elf_auxv_t;
  34
  35 /*
  36  * This is simiplar to the one in
  37  * native_client/src/untrusted/nacl/nacl_startup.h, but also supports 64 bit
  38  * pointers.
  39  */
  40 static Elf_auxv_t *nacl_startup_auxv(const uintptr_t info[]) {
  41   /* The layout of _start's argument is
  42    * info[0]: fini.
  43    * info[1]: envc
  44    * info[2]: argc
  45    * info[3]...[3+argc]: argv (NULL terminated)
  46    * info[3+argc+1]...[3+argc+1+envc]: envv (NULL terminated)
  47    * info[3+argc+1+envc+1]: auxv pairs.
  48    */
  49   int envc = info[1];
  50   int argc = info[2];
  51   return (Elf_auxv_t *) (info + 3 + envc + 1 + argc + 1);
  52 }
  53
  54 static void grok_auxv(const Elf_auxv_t *auxv) {
  55   const Elf_auxv_t *av;
  56   for (av = auxv; av->a_type != AT_NULL; ++av) {
  57     if (av->a_type == AT_SYSINFO) {
  58       __nacl_irt_query = (TYPE_nacl_irt_query) av->a_un.a_val;
  59     }
  60   }
  61 }
  62
  63 #define DO_QUERY(ident, name) __nacl_irt_query(ident, &name, sizeof(name))
  64
  65 static int my_strcmp(const char *a, const char *b) {
  66   while (*a == *b) {
  67     if (*a == '\0')
  68       return 0;
  69     ++a;
  70     ++b;
  71   }
  72   return (int) (unsigned char) *a - (int) (unsigned char) *b;
  73 }
  74
  75 static PP_Bool DidCreate(PP_Instance instance,
  76                          uint32_t argc,
  77                          const char* argn[],
  78                          const char* argv[]) {
  79   return 1;
  80 }
  81
  82 static void DidDestroy(PP_Instance instance) {
  83 }
  84
  85 static void DidChangeView(PP_Instance instance,
  86                           const struct PP_Rect* position,
  87                           const struct PP_Rect* clip) {
  88 }
  89
  90 static void DidChangeFocus(PP_Instance instance, PP_Bool has_focus) {
  91 }
  92
  93 static PP_Bool HandleDocumentLoad(PP_Instance instance,
  94                                   PP_Resource url_loader) {
  95   return 0;
  96 }
  97
  98 static int32_t MyPPP_InitializeModule(PP_Module module_id,
  99                                       PPB_GetInterface get_browser_interface) {
 100   return PP_OK;
 101 }
 102
 103 static void MyPPP_ShutdownModule(void) {
 104 }
 105
 106 static const void *MyPPP_GetInterface(const char *interface_name) {
 107   if (my_strcmp(interface_name, PPP_INSTANCE_INTERFACE_1_0) == 0)
 108     return &ppp_instance;
 109   return NULL;
 110 }
 111
 112 void _start(uintptr_t info[]) {
 113   Elf_auxv_t *auxv = nacl_startup_auxv(info);
 114   grok_auxv(auxv);
 115   DO_QUERY(NACL_IRT_BASIC_v0_1, __libnacl_irt_basic);
 116   DO_QUERY(NACL_IRT_DEV_FDIO_v0_1, __libnacl_irt_fdio);
 117
 118   struct nacl_irt_ppapihook ppapihook;
 119   DO_QUERY(NACL_IRT_PPAPIHOOK_v0_1, ppapihook);
 120
 121   /* This is local as a workaround to avoid having to apply
 122    * relocations to global variables. */
 123   struct PP_StartFunctions start_funcs = {
 124     MyPPP_InitializeModule,
 125     MyPPP_ShutdownModule,
 126     MyPPP_GetInterface,
 127   };
 128   /* Similarly, initialise some global variables, avoiding relocations. */
 129   struct PPP_Instance_1_0 local_ppp_instance = {
 130     DidCreate,
 131     DidDestroy,
 132     DidChangeView,
 133     DidChangeFocus,
 134     HandleDocumentLoad,
 135   };
 136   ppp_instance = local_ppp_instance;
 137
 138   ppapihook.ppapi_start(&start_funcs);
 139
 140   __libnacl_irt_basic.exit(0);
 141 }