The Tor Browser / file comparison
comparison: toolkit/crashreporter/google-breakpad/src/common/android/breakpad_getcontext.S
toolkit/crashreporter/google-breakpad/src/common/android/breakpad_getcontext.S
- branch
- TOR_BUG_3246
- changeset 7
- 129ffea94266
equal
deleted
inserted
replaced
| -1:000000000000 | 0:e496b4607552 |
|---|---|
| 1 // Copyright (c) 2012, Google Inc. | |
| 2 // All rights reserved. | |
| 3 // | |
| 4 // Redistribution and use in source and binary forms, with or without | |
| 5 // modification, are permitted provided that the following conditions are | |
| 6 // met: | |
| 7 // | |
| 8 // * Redistributions of source code must retain the above copyright | |
| 9 // notice, this list of conditions and the following disclaimer. | |
| 10 // * Redistributions in binary form must reproduce the above | |
| 11 // copyright notice, this list of conditions and the following disclaimer | |
| 12 // in the documentation and/or other materials provided with the | |
| 13 // distribution. | |
| 14 // * Neither the name of Google Inc. nor the names of its | |
| 15 // contributors may be used to endorse or promote products derived from | |
| 16 // this software without specific prior written permission. | |
| 17 // | |
| 18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | |
| 19 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | |
| 20 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | |
| 21 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT | |
| 22 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | |
| 23 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT | |
| 24 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
| 25 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
| 26 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
| 27 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | |
| 28 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
| 29 | |
| 30 // A minimalistic implementation of getcontext() to be used by | |
| 31 // Google Breakpad on Android. | |
| 32 | |
| 33 #include "common/android/ucontext_constants.h" | |
| 34 | |
| 35 /* int getcontext (ucontext_t *ucp) */ | |
| 36 | |
| 37 #ifdef __arm__ | |
| 38 | |
| 39 .text | |
| 40 .global breakpad_getcontext | |
| 41 .hidden breakpad_getcontext | |
| 42 .type breakpad_getcontext, #function | |
| 43 .align 0 | |
| 44 .fnstart | |
| 45 breakpad_getcontext: | |
| 46 | |
| 47 /* First, save r4-r11 */ | |
| 48 add r1, r0, #(MCONTEXT_GREGS_OFFSET + 4*4) | |
| 49 stm r1, {r4-r11} | |
| 50 | |
| 51 /* r12 is a scratch register, don't save it */ | |
| 52 | |
| 53 /* Save sp and lr explicitely. */ | |
| 54 /* - sp can't be stored with stmia in Thumb-2 */ | |
| 55 /* - STM instructions that store sp and pc are deprecated in ARM */ | |
| 56 str sp, [r0, #(MCONTEXT_GREGS_OFFSET + 13*4)] | |
| 57 str lr, [r0, #(MCONTEXT_GREGS_OFFSET + 14*4)] | |
| 58 | |
| 59 /* Save the caller's address in 'pc' */ | |
| 60 str lr, [r0, #(MCONTEXT_GREGS_OFFSET + 15*4)] | |
| 61 | |
| 62 /* Save ucontext_t* pointer accross next call */ | |
| 63 mov r4, r0 | |
| 64 | |
| 65 /* Call sigprocmask(SIG_BLOCK, NULL, &(ucontext->uc_sigmask)) */ | |
| 66 mov r0, #0 /* SIG_BLOCK */ | |
| 67 mov r1, #0 /* NULL */ | |
| 68 add r2, r4, #UCONTEXT_SIGMASK_OFFSET | |
| 69 bl sigprocmask(PLT) | |
| 70 | |
| 71 /* Intentionally do not save the FPU state here. This is because on | |
| 72 * Linux/ARM, one should instead use ptrace(PTRACE_GETFPREGS) or | |
| 73 * ptrace(PTRACE_GETVFPREGS) to get it. | |
| 74 * | |
| 75 * Note that a real implementation of getcontext() would need to save | |
| 76 * this here to allow setcontext()/swapcontext() to work correctly. | |
| 77 */ | |
| 78 | |
| 79 /* Restore the values of r4 and lr */ | |
| 80 mov r0, r4 | |
| 81 ldr lr, [r0, #(MCONTEXT_GREGS_OFFSET + 14*4)] | |
| 82 ldr r4, [r0, #(MCONTEXT_GREGS_OFFSET + 4*4)] | |
| 83 | |
| 84 /* Return 0 */ | |
| 85 mov r0, #0 | |
| 86 bx lr | |
| 87 | |
| 88 .fnend | |
| 89 .size breakpad_getcontext, . - breakpad_getcontext | |
| 90 | |
| 91 #elif defined(__i386__) | |
| 92 | |
| 93 .text | |
| 94 .global breakpad_getcontext | |
| 95 .hidden breakpad_getcontext | |
| 96 .align 4 | |
| 97 .type breakpad_getcontext, @function | |
| 98 | |
| 99 breakpad_getcontext: | |
| 100 | |
| 101 movl 4(%esp), %eax /* eax = uc */ | |
| 102 | |
| 103 /* Save register values */ | |
| 104 movl %ecx, MCONTEXT_ECX_OFFSET(%eax) | |
| 105 movl %edx, MCONTEXT_EDX_OFFSET(%eax) | |
| 106 movl %ebx, MCONTEXT_EBX_OFFSET(%eax) | |
| 107 movl %edi, MCONTEXT_EDI_OFFSET(%eax) | |
| 108 movl %esi, MCONTEXT_ESI_OFFSET(%eax) | |
| 109 movl %ebp, MCONTEXT_EBP_OFFSET(%eax) | |
| 110 | |
| 111 movl (%esp), %edx /* return address */ | |
| 112 lea 4(%esp), %ecx /* exclude return address from stack */ | |
| 113 mov %edx, MCONTEXT_EIP_OFFSET(%eax) | |
| 114 mov %ecx, MCONTEXT_ESP_OFFSET(%eax) | |
| 115 | |
| 116 xorl %ecx, %ecx | |
| 117 movw %fs, %cx | |
| 118 mov %ecx, MCONTEXT_FS_OFFSET(%eax) | |
| 119 | |
| 120 movl $0, MCONTEXT_EAX_OFFSET(%eax) | |
| 121 | |
| 122 /* Save floating point state to fpregstate, then update | |
| 123 * the fpregs pointer to point to it */ | |
| 124 leal UCONTEXT_FPREGS_MEM_OFFSET(%eax), %ecx | |
| 125 fnstenv (%ecx) | |
| 126 fldenv (%ecx) | |
| 127 mov %ecx, UCONTEXT_FPREGS_OFFSET(%eax) | |
| 128 | |
| 129 /* Save signal mask: sigprocmask(SIGBLOCK, NULL, &uc->uc_sigmask) */ | |
| 130 leal UCONTEXT_SIGMASK_OFFSET(%eax), %edx | |
| 131 xorl %ecx, %ecx | |
| 132 push %edx /* &uc->uc_sigmask */ | |
| 133 push %ecx /* NULL */ | |
| 134 push %ecx /* SIGBLOCK == 0 on i386 */ | |
| 135 call sigprocmask@PLT | |
| 136 addl $12, %esp | |
| 137 | |
| 138 movl $0, %eax | |
| 139 ret | |
| 140 | |
| 141 .size breakpad_getcontext, . - breakpad_getcontext | |
| 142 | |
| 143 #else | |
| 144 #error "This file has not been ported for your CPU!" | |
| 145 #endif |
