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-rw-r--r--sysdeps/unix/sysv/linux/bits/sigstksz.h33
-rw-r--r--sysdeps/unix/sysv/linux/ia64/sysconf-sigstksz.h27
-rw-r--r--sysdeps/unix/sysv/linux/sysconf-sigstksz.h38
-rw-r--r--sysdeps/unix/sysv/linux/sysconf.c9
-rw-r--r--sysdeps/unix/sysv/linux/x86/dl-minsigstacksize.h83
-rw-r--r--sysdeps/unix/sysv/linux/x86/include/bits/sigstack.h5
6 files changed, 195 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/bits/sigstksz.h b/sysdeps/unix/sysv/linux/bits/sigstksz.h
new file mode 100644
index 0000000000..926508f2b4
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/bits/sigstksz.h
@@ -0,0 +1,33 @@
+/* Definition of MINSIGSTKSZ and SIGSTKSZ.  Linux version.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _SIGNAL_H
+# error "Never include <bits/sigstksz.h> directly; use <signal.h> instead."
+#endif
+
+#if defined __USE_SC_SIGSTKSZ && __USE_SC_SIGSTKSZ
+# include <unistd.h>
+
+/* Default stack size for a signal handler: sysconf (SC_SIGSTKSZ).  */
+# undef SIGSTKSZ
+# define SIGSTKSZ sysconf (_SC_SIGSTKSZ)
+
+/* Minimum stack size for a signal handler: SIGSTKSZ.  */
+# undef MINSIGSTKSZ
+# define MINSIGSTKSZ SIGSTKSZ
+#endif
diff --git a/sysdeps/unix/sysv/linux/ia64/sysconf-sigstksz.h b/sysdeps/unix/sysv/linux/ia64/sysconf-sigstksz.h
new file mode 100644
index 0000000000..7e5ceba151
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/ia64/sysconf-sigstksz.h
@@ -0,0 +1,27 @@
+/* sysconf_sigstksz ().  Linux/ia64 version.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* Return sysconf (_SC_SIGSTKSZ).  */
+
+static long int
+sysconf_sigstksz (void)
+{
+  _Static_assert (__builtin_constant_p (SIGSTKSZ),
+		  "SIGSTKSZ is constant");
+  return SIGSTKSZ;
+}
diff --git a/sysdeps/unix/sysv/linux/sysconf-sigstksz.h b/sysdeps/unix/sysv/linux/sysconf-sigstksz.h
new file mode 100644
index 0000000000..64d450b22c
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/sysconf-sigstksz.h
@@ -0,0 +1,38 @@
+/* sysconf_sigstksz ().  Linux version.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* Return sysconf (_SC_SIGSTKSZ).  */
+
+static long int
+sysconf_sigstksz (void)
+{
+  long int minsigstacksize = GLRO(dl_minsigstacksize);
+  assert (minsigstacksize != 0);
+  _Static_assert (__builtin_constant_p (MINSIGSTKSZ),
+		  "MINSIGSTKSZ is constant");
+  if (minsigstacksize < MINSIGSTKSZ)
+    minsigstacksize = MINSIGSTKSZ;
+  /* MAX (MINSIGSTKSZ, sysconf (_SC_MINSIGSTKSZ)) * 4.  */
+  long int sigstacksize = minsigstacksize * 4;
+  /* Return MAX (SIGSTKSZ, sigstacksize).  */
+  _Static_assert (__builtin_constant_p (SIGSTKSZ),
+		  "SIGSTKSZ is constant");
+  if (sigstacksize < SIGSTKSZ)
+    sigstacksize = SIGSTKSZ;
+  return sigstacksize;
+}
diff --git a/sysdeps/unix/sysv/linux/sysconf.c b/sysdeps/unix/sysv/linux/sysconf.c
index bfad5b6858..366fcef01e 100644
--- a/sysdeps/unix/sysv/linux/sysconf.c
+++ b/sysdeps/unix/sysv/linux/sysconf.c
@@ -16,6 +16,7 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
+#include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <stdlib.h>
@@ -26,6 +27,7 @@
 #include <sys/param.h>
 #include <not-cancel.h>
 #include <ldsodefs.h>
+#include <sysconf-sigstksz.h>
 
 /* Legacy value of ARG_MAX.  The macro is now not defined since the
    actual value varies based on the stack size.  */
@@ -75,6 +77,13 @@ __sysconf (int name)
       }
       break;
 
+    case _SC_MINSIGSTKSZ:
+      assert (GLRO(dl_minsigstacksize) != 0);
+      return GLRO(dl_minsigstacksize);
+
+    case _SC_SIGSTKSZ:
+      return sysconf_sigstksz ();
+
     default:
       break;
     }
diff --git a/sysdeps/unix/sysv/linux/x86/dl-minsigstacksize.h b/sysdeps/unix/sysv/linux/x86/dl-minsigstacksize.h
new file mode 100644
index 0000000000..6088bbc99e
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86/dl-minsigstacksize.h
@@ -0,0 +1,83 @@
+/* Emulate AT_MINSIGSTKSZ.  Linux/x86 version.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* Emulate AT_MINSIGSTKSZ with XSAVE. */
+
+static inline void
+dl_check_minsigstacksize (const struct cpu_features *cpu_features)
+{
+  /* Return if AT_MINSIGSTKSZ is provide by kernel.  */
+  if (GLRO(dl_minsigstacksize) != 0)
+    return;
+
+  if (cpu_features->basic.max_cpuid >= 0xd
+      && CPU_FEATURES_CPU_P (cpu_features, OSXSAVE))
+    {
+      /* Emulate AT_MINSIGSTKSZ.  In Linux kernel, the signal frame data
+	 with XSAVE is composed of the following areas and laid out as:
+	 ------------------------------
+	 | alignment padding          |
+	 ------------------------------
+	 | xsave buffer               |
+	 ------------------------------
+	 | fsave header (32-bit only) |
+	 ------------------------------
+	 | siginfo + ucontext         |
+	 ------------------------------
+	 */
+
+      unsigned int sigframe_size;
+
+#ifdef __x86_64__
+      /* NB: sizeof(struct rt_sigframe) + 8-byte return address in Linux
+	 kernel.  */
+      sigframe_size = 440 + 8;
+#else
+      /* NB: sizeof(struct sigframe_ia32) + sizeof(struct fregs_state)) +
+	 4-byte return address + 3 * 4-byte arguments in Linux kernel.  */
+      sigframe_size = 736 + 112 + 4 + 3 * 4;
+#endif
+
+      /* Add 15 bytes to align the stack to 16 bytes.  */
+      sigframe_size += 15;
+
+      /* Make the space before xsave buffer multiple of 16 bytes.  */
+      sigframe_size = ALIGN_UP (sigframe_size, 16);
+
+      /* Add (64 - 16)-byte padding to align xsave buffer at 64 bytes.  */
+      sigframe_size += 64 - 16;
+
+      unsigned int eax, ebx, ecx, edx;
+      __cpuid_count (0xd, 0, eax, ebx, ecx, edx);
+
+      /* Add the size of xsave buffer.  */
+      sigframe_size += ebx;
+
+      /* Add the size of FP_XSTATE_MAGIC2.  */
+#define FP_XSTATE_MAGIC2 0x46505845U
+      sigframe_size += sizeof (FP_XSTATE_MAGIC2);
+
+      GLRO(dl_minsigstacksize) = sigframe_size;
+    }
+  else
+    {
+      /* NB: Default to a constant MINSIGSTKSZ.  */
+      _Static_assert (__builtin_constant_p (MINSIGSTKSZ),
+		      "MINSIGSTKSZ is constant");
+      GLRO(dl_minsigstacksize) = MINSIGSTKSZ;
+    }
+}
diff --git a/sysdeps/unix/sysv/linux/x86/include/bits/sigstack.h b/sysdeps/unix/sysv/linux/x86/include/bits/sigstack.h
new file mode 100644
index 0000000000..208754c497
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86/include/bits/sigstack.h
@@ -0,0 +1,5 @@
+#include_next <bits/sigstack.h>
+
+#ifndef _ISOMAC
+# define CONSTANT_MINSIGSTKSZ 0
+#endif
generated by cgit-pink 1.4.1 (git 2.36.1) at 2024-07-08 10:09:15 +0000