diff options
| author | Vincent Ambo <tazjin@google.com> | 2020-05-27T00·26+0100 |
|---|---|---|
| committer | Vincent Ambo <tazjin@google.com> | 2020-05-27T00·26+0100 |
| commit | afe04691aca3f669f517adaeb5bd4a87a481fb4a (patch) | |
| tree | 60ae6c91a3959b2f6486256e26ff126e598d1e5d /m4/pc_from_ucontext.m4 | |
Squashed 'third_party/glog/' content from commit 9ef754a3023
git-subtree-dir: third_party/glog git-subtree-split: 9ef754a3023e6fd10f20fe53dfca96dd898182e3
Diffstat (limited to 'm4/pc_from_ucontext.m4')
| -rw-r--r-- | m4/pc_from_ucontext.m4 | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/m4/pc_from_ucontext.m4 b/m4/pc_from_ucontext.m4 new file mode 100644 index 000000000000..daffddb536fd --- /dev/null +++ b/m4/pc_from_ucontext.m4 @@ -0,0 +1,71 @@ +# We want to access the "PC" (Program Counter) register from a struct +# ucontext. Every system has its own way of doing that. We try all the +# possibilities we know about. Note REG_PC should come first (REG_RIP +# is also defined on solaris, but does the wrong thing). + +# OpenBSD doesn't have ucontext.h, but we can get PC from ucontext_t +# by using signal.h. + +# The first argument of AC_PC_FROM_UCONTEXT will be invoked when we +# cannot find a way to obtain PC from ucontext. + +AC_DEFUN([AC_PC_FROM_UCONTEXT], + [AC_CHECK_HEADERS(ucontext.h) + AC_CHECK_HEADERS(sys/ucontext.h) # ucontext on OS X 10.6 (at least) + AC_MSG_CHECKING([how to access the program counter from a struct ucontext]) + pc_fields=" uc_mcontext.gregs[[REG_PC]]" # Solaris x86 (32 + 64 bit) + pc_fields="$pc_fields uc_mcontext.gregs[[REG_EIP]]" # Linux (i386) + pc_fields="$pc_fields uc_mcontext.gregs[[REG_RIP]]" # Linux (x86_64) + pc_fields="$pc_fields uc_mcontext.sc_ip" # Linux (ia64) + pc_fields="$pc_fields uc_mcontext.uc_regs->gregs[[PT_NIP]]" # Linux (ppc) + pc_fields="$pc_fields uc_mcontext.gregs[[R15]]" # Linux (arm old [untested]) + pc_fields="$pc_fields uc_mcontext.arm_pc" # Linux (arm new [untested]) + pc_fields="$pc_fields uc_mcontext.mc_eip" # FreeBSD (i386) + pc_fields="$pc_fields uc_mcontext.mc_rip" # FreeBSD (x86_64 [untested]) + pc_fields="$pc_fields uc_mcontext.__gregs[[_REG_EIP]]" # NetBSD (i386) + pc_fields="$pc_fields uc_mcontext.__gregs[[_REG_RIP]]" # NetBSD (x86_64) + pc_fields="$pc_fields uc_mcontext->ss.eip" # OS X (i386, <=10.4) + pc_fields="$pc_fields uc_mcontext->__ss.__eip" # OS X (i386, >=10.5) + pc_fields="$pc_fields uc_mcontext->ss.rip" # OS X (x86_64) + pc_fields="$pc_fields uc_mcontext->__ss.__rip" # OS X (>=10.5 [untested]) + pc_fields="$pc_fields uc_mcontext->ss.srr0" # OS X (ppc, ppc64 [untested]) + pc_fields="$pc_fields uc_mcontext->__ss.__srr0" # OS X (>=10.5 [untested]) + pc_field_found=false + for pc_field in $pc_fields; do + if ! $pc_field_found; then + if test "x$ac_cv_header_sys_ucontext_h" = xyes; then + AC_TRY_COMPILE([#define _GNU_SOURCE 1 + #include <sys/ucontext.h>], + [ucontext_t u; return u.$pc_field == 0;], + AC_DEFINE_UNQUOTED(PC_FROM_UCONTEXT, $pc_field, + How to access the PC from a struct ucontext) + AC_MSG_RESULT([$pc_field]) + pc_field_found=true) + else + AC_TRY_COMPILE([#define _GNU_SOURCE 1 + #include <ucontext.h>], + [ucontext_t u; return u.$pc_field == 0;], + AC_DEFINE_UNQUOTED(PC_FROM_UCONTEXT, $pc_field, + How to access the PC from a struct ucontext) + AC_MSG_RESULT([$pc_field]) + pc_field_found=true) + fi + fi + done + if ! $pc_field_found; then + pc_fields=" sc_eip" # OpenBSD (i386) + pc_fields="$pc_fields sc_rip" # OpenBSD (x86_64) + for pc_field in $pc_fields; do + if ! $pc_field_found; then + AC_TRY_COMPILE([#include <signal.h>], + [ucontext_t u; return u.$pc_field == 0;], + AC_DEFINE_UNQUOTED(PC_FROM_UCONTEXT, $pc_field, + How to access the PC from a struct ucontext) + AC_MSG_RESULT([$pc_field]) + pc_field_found=true) + fi + done + fi + if ! $pc_field_found; then + [$1] + fi]) |