Modularize the libdimension codebase.

2 files changed, 230 insertions, 0 deletions

diff --git a/libdimension/platform/platform.c b/libdimension/platform/platform.c
new file mode 100644
index 0000000..84d9bf0
--- /dev/null
+++ b/libdimension/platform/platform.c
@@ -0,0 +1,187 @@
+/*************************************************************************
+ * Copyright (C) 2010-2014 Tavian Barnes <tavianator@tavianator.com>     *
+ *                                                                       *
+ * This file is part of The Dimension Library.                           *
+ *                                                                       *
+ * The Dimension 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 3 of the *
+ * License, or (at your option) any later version.                       *
+ *                                                                       *
+ * The Dimension 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 this program.  If not, see                         *
+ * <http://www.gnu.org/licenses/>.                                       *
+ *************************************************************************/
+
+/**
+ * @file
+ * Platform abstractions.
+ */
+
+#define _GNU_SOURCE
+#include "internal.h"
+#include "internal/platform.h"
+#include "dimension/platform.h"
+
+#if HAVE_UNISTD_H
+  #include <unistd.h>
+#endif
+#ifdef _WIN32
+  #include <windows.h>
+#endif
+#if DMNSN_BACKTRACE
+  #include <execinfo.h>    // For backtrace() etc.
+#endif
+#if DMNSN_GETTID
+  #include <sys/syscall.h> // For gettid() where supported
+#endif
+#if DMNSN_SCHED_GETAFFINITY
+  #include <sched.h>       // For sched_getaffinity()
+#endif
+#if DMNSN_TIMES
+  #include <sys/times.h>
+#endif
+#if DMNSN_GETRUSAGE
+  #include <sys/time.h>
+  #include <sys/resource.h>
+#endif
+
+void
+dmnsn_backtrace(FILE *file)
+{
+#if DMNSN_BACKTRACE
+#define DMNSN_BACKTRACE_SIZE 128
+  void *buffer[DMNSN_BACKTRACE_SIZE];
+
+  int nptrs = backtrace(buffer, DMNSN_BACKTRACE_SIZE);
+  int fd = fileno(file);
+  if (fd != -1) {
+    backtrace_symbols_fd(buffer, nptrs, fd);
+  }
+#endif
+}
+
+bool
+dmnsn_is_main_thread(void)
+{
+#if DMNSN_GETTID
+  return getpid() == syscall(SYS_gettid);
+#else
+  return true;
+#endif
+}
+
+bool
+dmnsn_is_little_endian(void)
+{
+  // Undefined behaviour, but quite portable
+  union {
+    unsigned int i;
+    unsigned char c;
+  } u = { .i = 1 };
+  return u.c == 1;
+}
+
+size_t
+dmnsn_ncpus(void)
+{
+#if DMNSN_SCHED_GETAFFINITY
+  cpu_set_t cpuset;
+  if (sched_getaffinity(0, sizeof(cpuset), &cpuset) == 0) {
+    return CPU_COUNT(&cpuset);
+  } else {
+    dmnsn_warning("sched_getaffinity() failed.");
+    return 1;
+  }
+#elif DMNSN_SC_NPROCESSORS_ONLN
+  long nprocs = sysconf(_SC_NPROCESSORS_ONLN);
+  if (nprocs > 0) {
+    return nprocs;
+  } else {
+    dmnsn_warning("sysconf(_SC_NPROCESSORS_ONLN) failed.");
+    return 1;
+  }
+#elif defined(_WIN32)
+  SYSTEM_INFO sysinfo;
+  GetSystemInfo(&sysinfo);
+  return sysinfo.dwNumberOfProcessors;
+#else
+  return 1;
+#endif
+}
+
+#if DMNSN_GETRUSAGE
+/// Convert a struct timeval to a double.
+static inline double
+dmnsn_timeval2double(struct timeval tv)
+{
+  return tv.tv_sec + tv.tv_usec/1.0e6;
+}
+#endif
+
+void
+dmnsn_get_times(dmnsn_timer *timer)
+{
+#if DMNSN_GETRUSAGE
+  struct timeval real;
+  gettimeofday(&real, NULL);
+
+  struct rusage usage;
+  if (getrusage(RUSAGE_SELF, &usage) == 0) {
+    timer->real   = dmnsn_timeval2double(real);
+    timer->user   = dmnsn_timeval2double(usage.ru_utime);
+    timer->system = dmnsn_timeval2double(usage.ru_stime);
+  } else {
+    dmnsn_warning("getrusage() failed.");
+    timer->real = timer->user = timer->system = 0.0;
+  }
+#elif DMNSN_TIMES
+  static long clk_tck = 0;
+
+  // Figure out the clock ticks per second
+  if (!clk_tck) {
+    clk_tck = sysconf(_SC_CLK_TCK);
+    if (clk_tck == -1) {
+      dmnsn_warning("sysconf(_SC_CLK_TCK) failed.");
+      clk_tck = 1000000L;
+    }
+  }
+
+  struct tms buf;
+  clock_t real = times(&buf);
+  if (real == (clock_t)-1) {
+    dmnsn_warning("times() failed.");
+    timer->real = timer->user = timer->system = 0.0;
+  } else {
+    timer->real   = (double)real/clk_tck;
+    timer->user   = (double)buf.tms_utime/clk_tck;
+    timer->system = (double)buf.tms_stime/clk_tck;
+  }
+#elif defined(_WIN32)
+  FILETIME real;
+  GetSystemTimeAsFileTime(&real);
+
+  FILETIME user, system, creation, exit;
+  HANDLE current_process = GetCurrentProcess();
+  if (GetProcessTimes(current_process,
+                      &creation, &exit, &system, &user) != 0)
+  {
+    timer->real
+      = (((uint64_t)real.dwHighDateTime << 32) + real.dwLowDateTime)/1.0e7;
+    timer->user
+      = (((uint64_t)user.dwHighDateTime << 32) + user.dwLowDateTime)/1.0e7;
+    timer->system
+      = (((uint64_t)system.dwHighDateTime << 32) + system.dwLowDateTime)/1.0e7;
+  } else {
+    dmnsn_warning("GetProcessTimes() failed.");
+    timer->real = timer->user = timer->system = 0.0;
+  }
+#else
+  timer->real = timer->user = timer->system = 0.0;
+#endif
+}
diff --git a/libdimension/platform/timer.c b/libdimension/platform/timer.c
new file mode 100644
index 0000000..2d91469
--- /dev/null
+++ b/libdimension/platform/timer.c
@@ -0,0 +1,43 @@
+/*************************************************************************
+ * Copyright (C) 2010-2011 Tavian Barnes <tavianator@tavianator.com>     *
+ *                                                                       *
+ * This file is part of The Dimension Library.                           *
+ *                                                                       *
+ * The Dimension 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 3 of the *
+ * License, or (at your option) any later version.                       *
+ *                                                                       *
+ * The Dimension 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 this program.  If not, see                         *
+ * <http://www.gnu.org/licenses/>.                                       *
+ *************************************************************************/
+
+/**
+ * @file
+ * Performance counter.
+ */
+
+#include "internal/platform.h"
+#include "dimension/platform.h"
+
+void
+dmnsn_timer_start(dmnsn_timer *timer)
+{
+  dmnsn_get_times(timer);
+}
+
+void
+dmnsn_timer_stop(dmnsn_timer *timer)
+{
+  dmnsn_timer now;
+  dmnsn_get_times(&now);
+  timer->real   = now.real   - timer->real;
+  timer->user   = now.user   - timer->user;
+  timer->system = now.system - timer->system;
+}