Enhance FPM trace checking

- Cross-compilation enhancements to be able to set PROC_MEM_FILE
- mach_vm_read check simplified as the signature is a bit different
  vm_map_read_t vs vm_map_t first argument. The `check_symbol_exists()`
  is sufficient check in this case and avoids writing entire signature.
- The toolchains template improved and refactored
- Fixed some nits in FindNetSnmp module

Author: petk

cmake/cmake/modules/FindNetSnmp.cmake

@@ -5,20 +5,20 @@ Module defines the following `IMPORTED` target(s):
 
 * `NetSnmp::NetSnmp` - The package library, if found.
 
-Result variables:
+## Result variables
 
 * `NetSnmp_FOUND` - Whether the package has been found.
 *` NetSnmp_INCLUDE_DIRS` - Include directories needed to use this package.
 *` NetSnmp_LIBRARIES` - Libraries needed to link to the package library.
 * `NetSnmp_VERSION` - Package version, if found.
 
-Cache variables:
+## Cache variables
 
 * `NetSnmp_INCLUDE_DIR` - Directory containing package library headers.
 * `NetSnmp_LIBRARY` - The path to the package library.
 * `NetSnmp_EXECUTABLE` - Path to net-snmp-config utility.
 
-Hints:
+## Hints
 
 The `NetSnmp_ROOT` variable adds custom search path.
 #]=============================================================================]
@@ -60,13 +60,19 @@ if(NetSnmp_EXECUTABLE)
     string(APPEND _netsnmp_config_include_dir "/include")
   endif()
 
-  # TODO: To be added.
+  # TODO: To be added when linking static NetSnmp library.
   execute_process(
     COMMAND "${NetSnmp_EXECUTABLE}" --external-libs
     OUTPUT_VARIABLE _netsnmp_config_external_libraries
     OUTPUT_STRIP_TRAILING_WHITESPACE
     ERROR_QUIET
   )
+  separate_arguments(
+    _netsnmp_config_external_libraries
+    NATIVE_COMMAND
+    "${_netsnmp_config_external_libraries}"
+  )
+  list(FILTER _netsnmp_config_external_libraries INCLUDE REGEX "^(-L|-l)")
 
   execute_process(
     COMMAND "${NetSnmp_EXECUTABLE}" --libdir

cmake/cmake/modules/PHP/CheckPtrace.cmake

@@ -1,154 +1,147 @@
 #[=============================================================================[
 Check for ptrace().
 
-Result variables:
-
-* `PHP_TRACE_TYPE`
-  Name of the trace type that should be used in FPM.
-
-Cache variables:
+## Cache variables:
 
 * `HAVE_PTRACE`
+
   Whether `ptrace()` is present and working as expected.
+
 * `HAVE_MACH_VM_READ`
+
   Whether `ptrace()` didn't work and the `mach_vm_read()` is present.
+
+## Result variables
+
 * `PROC_MEM_FILE`
-  String of the `/proc/pid/mem` interface.
+
+  If neither `ptrace()` or mach_vm_read()` works, the `/proc/pid/<file>`
+  interface (`mem` or `as`) is set if found and works as expected.
 #]=============================================================================]
 
 include_guard(GLOBAL)
 
 include(CheckSourceCompiles)
 include(CheckSourceRuns)
+include(CheckSymbolExists)
 include(CMakePushCheckState)
 
-message(CHECK_START "Checking for ptrace")
-check_source_compiles(C [[
-  #include <sys/types.h>
-  #include <sys/ptrace.h>
-
-  int main(void)
-  {
-    ptrace(0, 0, (void *) 0, 0);
-    return 0;
-  }
-]] _have_ptrace)
-if(_have_ptrace)
-  message(CHECK_PASS "yes")
-else()
-  message(CHECK_FAIL "no")
-endif()
+message(CHECK_START "Checking whether ptrace works")
 
-if(_have_ptrace)
-  message(CHECK_START "Checking whether ptrace works")
-  check_source_runs(C [[
-    #include <unistd.h>
-    #include <signal.h>
-    #include <sys/wait.h>
+cmake_push_check_state(RESET)
+  set(CMAKE_REQUIRED_QUIET TRUE)
+  check_source_compiles(C [[
     #include <sys/types.h>
     #include <sys/ptrace.h>
-    #include <errno.h>
-
-    #if !defined(PTRACE_ATTACH) && defined(PT_ATTACH)
-    #define PTRACE_ATTACH PT_ATTACH
-    #endif
-
-    #if !defined(PTRACE_DETACH) && defined(PT_DETACH)
-    #define PTRACE_DETACH PT_DETACH
-    #endif
-
-    #if !defined(PTRACE_PEEKDATA) && defined(PT_READ_D)
-    #define PTRACE_PEEKDATA PT_READ_D
-    #endif
 
     int main(void)
     {
-      /* copy will fail if sizeof(long) == 8 and we've got "int ptrace()" */
-      long v1 = (unsigned int) -1;
-      long v2;
-      pid_t child;
-      int status;
+      ptrace(0, 0, (void *) 0, 0);
+      return 0;
+    }
+  ]] _HAVE_PTRACE)
+cmake_pop_check_state()
+
+if(_HAVE_PTRACE)
+  cmake_push_check_state(RESET)
+    set(CMAKE_REQUIRED_QUIET TRUE)
+    check_source_runs(C [[
+      #include <unistd.h>
+      #include <signal.h>
+      #include <sys/wait.h>
+      #include <sys/types.h>
+      #include <sys/ptrace.h>
+      #include <errno.h>
+
+      #if !defined(PTRACE_ATTACH) && defined(PT_ATTACH)
+      # define PTRACE_ATTACH PT_ATTACH
+      #endif
+
+      #if !defined(PTRACE_DETACH) && defined(PT_DETACH)
+      # define PTRACE_DETACH PT_DETACH
+      #endif
+
+      #if !defined(PTRACE_PEEKDATA) && defined(PT_READ_D)
+      # define PTRACE_PEEKDATA PT_READ_D
+      #endif
+
+      int main(void)
+      {
+        /* copy will fail if sizeof(long) == 8 and we've got "int ptrace()" */
+        long v1 = (unsigned int) -1;
+        long v2;
+        pid_t child;
+        int status;
+
+        if ( (child = fork()) ) { /* parent */
+          int ret = 0;
+
+          if (0 > ptrace(PTRACE_ATTACH, child, 0, 0)) {
+            return 2;
+          }
 
-      if ( (child = fork()) ) { /* parent */
-        int ret = 0;
+          waitpid(child, &status, 0);
 
-        if (0 > ptrace(PTRACE_ATTACH, child, 0, 0)) {
-          return 2;
-        }
+      #ifdef PT_IO
+          struct ptrace_io_desc ptio = {
+            .piod_op = PIOD_READ_D,
+            .piod_offs = &v1,
+            .piod_addr = &v2,
+            .piod_len = sizeof(v1)
+          };
 
-        waitpid(child, &status, 0);
+          if (0 > ptrace(PT_IO, child, (void *) &ptio, 0)) {
+            ret = 3;
+          }
+      #else
+          errno = 0;
 
-    #ifdef PT_IO
-        struct ptrace_io_desc ptio = {
-          .piod_op = PIOD_READ_D,
-          .piod_offs = &v1,
-          .piod_addr = &v2,
-          .piod_len = sizeof(v1)
-        };
+          v2 = ptrace(PTRACE_PEEKDATA, child, (void *) &v1, 0);
 
-        if (0 > ptrace(PT_IO, child, (void *) &ptio, 0)) {
-          ret = 3;
-        }
-    #else
-        errno = 0;
+          if (errno) {
+            ret = 4;
+          }
+      #endif
+          ptrace(PTRACE_DETACH, child, (void *) 1, 0);
 
-        v2 = ptrace(PTRACE_PEEKDATA, child, (void *) &v1, 0);
+          kill(child, SIGKILL);
 
-        if (errno) {
-          ret = 4;
+          return ret ? ret : (v1 != v2);
+        } else { /* child */
+          sleep(10);
+          return 0;
         }
-    #endif
-        ptrace(PTRACE_DETACH, child, (void *) 1, 0);
-
-        kill(child, SIGKILL);
-
-        return ret ? ret : (v1 != v2);
-      } else { /* child */
-        sleep(10);
-        return 0;
       }
-    }
-  ]] HAVE_PTRACE)
+    ]] HAVE_PTRACE)
+  cmake_pop_check_state()
+endif()
 
-  if(HAVE_PTRACE)
-    message(CHECK_PASS "yes")
-  else()
-    message(CHECK_FAIL "no")
-  endif()
+if(HAVE_PTRACE)
+  message(CHECK_PASS "yes")
+  return()
 endif()
+message(CHECK_FAIL "no")
 
-if(NOT HAVE_PTRACE)
-  check_source_compiles(C [[
-    #include <mach/mach.h>
-    #include <mach/mach_vm.h>
+check_symbol_exists(mach_vm_read "mach/mach.h;mach/mach_vm.h" HAVE_MACH_VM_READ)
 
-    int main(void)
-    {
-      mach_vm_read(
-        (vm_map_t)0,
-        (mach_vm_address_t)0,
-        (mach_vm_size_t)0,
-        (vm_offset_t *)0,
-        (mach_msg_type_number_t*)0
-      );
-      return 0;
-    }
-  ]] HAVE_MACH_VM_READ)
+if(HAVE_MACH_VM_READ)
+  return()
 endif()
 
-# TODO: Check if /proc/self is sufficient location instead of the /proc/$$ as in
-# Autoconf.
-message(CHECK_START "Checking for proc mem file")
-if(EXISTS /proc/self/mem)
-  set(_php_proc_mem_file "mem")
-elseif(EXISTS /proc/self/as)
-  set(_php_proc_mem_file "as")
-endif()
+message(CHECK_START "Checking for process memory access file")
+
+if(NOT CMAKE_CROSSCOMPILING)
+  set(PROC_MEM_FILE)
+  if(EXISTS /proc/self/mem)
+    set(PROC_MEM_FILE "mem")
+  elseif(EXISTS /proc/self/as)
+    set(PROC_MEM_FILE "as")
+  endif()
 
-if(_php_proc_mem_file)
-  if(NOT CMAKE_CROSSCOMPILING)
+  if(PROC_MEM_FILE)
     cmake_push_check_state(RESET)
       set(CMAKE_REQUIRED_DEFINITIONS -D_GNU_SOURCE)
+      set(CMAKE_REQUIRED_QUIET TRUE)
       check_source_runs(C "
         #define _FILE_OFFSET_BITS 64
         #include <stdint.h>
@@ -163,7 +156,7 @@ if(_php_proc_mem_file)
           long v1 = (unsigned int) -1, v2 = 0;
           char buf[128];
           int fd;
-          sprintf(buf, \"/proc/%d/${_php_proc_mem_file}\", getpid());
+          sprintf(buf, \"/proc/%d/${PROC_MEM_FILE}\", getpid());
           fd = open(buf, O_RDONLY);
           if (0 > fd) {
             return 1;
@@ -175,29 +168,20 @@ if(_php_proc_mem_file)
           close(fd);
           return v1 != v2;
         }
-      " _php_proc_mem_successful)
+      " _HAVE_PROC_MEM_FILE)
     cmake_pop_check_state()
+
+    if(NOT _HAVE_PROC_MEM_FILE)
+      unset(PROC_MEM_FILE)
+    endif()
   endif()
 endif()
 
-if(_php_proc_mem_file AND _php_proc_mem_successful)
-  set(
-    PROC_MEM_FILE "${_php_proc_mem_file}"
-    CACHE INTERNAL "/proc/pid/mem interface"
-  )
+if(PROC_MEM_FILE)
+  message(CHECK_PASS "yes (${PROC_MEM_FILE})")
+  return()
 endif()
 
-if(HAVE_PTRACE)
-  set(PHP_TRACE_TYPE "ptrace")
-elseif(_php_proc_mem_file)
-  set(PHP_TRACE_TYPE "pread")
-elseif(HAVE_MACH_VM_READ)
-  set(PHP_TRACE_TYPE "mach")
-endif()
+message(CHECK_FAIL "no")
 
-if(PHP_TRACE_TYPE)
-  message(CHECK_PASS "${PHP_TRACE_TYPE}")
-else()
-  message(CHECK_FAIL "not found")
-  message(WARNING "FPM Trace - ptrace, pread, or mach: could not be found")
-endif()
+message(WARNING "FPM trace - ptrace, pread, or mach: could not be found")