Add cpu_count to System module (#4449)

Signed-off-by: Mike Fiedler <miketheman@gmail.com>
crystal-lang · May 24, 2017 · 0e73cf4 · 0e73cf4
1 parent 5aa3b15
commit 0e73cf4
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Showing 11 changed files with 71 additions and 45 deletions.
diff --git a/spec/std/system_spec.cr b/spec/std/system_spec.cr
@@ -10,4 +10,12 @@ describe System do
       hostname.should eq(shell_hostname)
     end
   end
+
+  describe "cpu_count" do
+    it "returns current CPU count" do
+      shell_cpus = `getconf _NPROCESSORS_ONLN || nproc --all || grep -c '^processor' /proc/cpuinfo`.to_i
+      cpu_count = System.cpu_count
+      cpu_count.should eq(shell_cpus)
+    end
+  end
 end
diff --git a/src/lib_c/aarch64-linux-gnu/c/unistd.cr b/src/lib_c/aarch64-linux-gnu/c/unistd.cr
@@ -2,11 +2,12 @@ require "./sys/types"
 require "./stdint"
 
 lib LibC
-  F_OK       = 0
-  R_OK       = 4
-  W_OK       = 2
-  X_OK       = 1
-  SC_CLK_TCK = 2
+  F_OK                =  0
+  R_OK                =  4
+  W_OK                =  2
+  X_OK                =  1
+  SC_CLK_TCK          =  2
+  SC_NPROCESSORS_ONLN = 84
 
   fun access(name : Char*, type : Int) : Int
   fun chdir(path : Char*) : Int

diff --git a/src/lib_c/amd64-unknown-openbsd/c/unistd.cr b/src/lib_c/amd64-unknown-openbsd/c/unistd.cr
@@ -2,11 +2,12 @@ require "./sys/types"
 require "./stdint"
 
 lib LibC
-  F_OK       =    0
-  R_OK       = 0x04
-  W_OK       = 0x02
-  X_OK       = 0x01
-  SC_CLK_TCK =    3
+  F_OK                =    0
+  R_OK                = 0x04
+  W_OK                = 0x02
+  X_OK                = 0x01
+  SC_CLK_TCK          =    3
+  SC_NPROCESSORS_ONLN =   58
 
   fun access(x0 : Char*, x1 : Int) : Int
   fun chdir(x0 : Char*) : Int

diff --git a/src/lib_c/arm-linux-gnueabihf/c/unistd.cr b/src/lib_c/arm-linux-gnueabihf/c/unistd.cr
@@ -2,11 +2,12 @@ require "./sys/types"
 require "./stdint"
 
 lib LibC
-  F_OK       = 0
-  R_OK       = 4
-  W_OK       = 2
-  X_OK       = 1
-  SC_CLK_TCK = 2
+  F_OK                =  0
+  R_OK                =  4
+  W_OK                =  2
+  X_OK                =  1
+  SC_CLK_TCK          =  2
+  SC_NPROCESSORS_ONLN = 58
 
   fun access(name : Char*, type : Int) : Int
   fun chdir(path : Char*) : Int

diff --git a/src/lib_c/i686-linux-gnu/c/unistd.cr b/src/lib_c/i686-linux-gnu/c/unistd.cr
@@ -2,11 +2,12 @@ require "./sys/types"
 require "./stdint"
 
 lib LibC
-  F_OK       = 0
-  R_OK       = 4
-  W_OK       = 2
-  X_OK       = 1
-  SC_CLK_TCK = 2
+  F_OK                =  0
+  R_OK                =  4
+  W_OK                =  2
+  X_OK                =  1
+  SC_CLK_TCK          =  2
+  SC_NPROCESSORS_ONLN = 84
 
   fun access(name : Char*, type : Int) : Int
   fun chdir(path : Char*) : Int

diff --git a/src/lib_c/i686-linux-musl/c/unistd.cr b/src/lib_c/i686-linux-musl/c/unistd.cr
@@ -2,11 +2,12 @@ require "./sys/types"
 require "./stdint"
 
 lib LibC
-  F_OK       = 0
-  R_OK       = 4
-  W_OK       = 2
-  X_OK       = 1
-  SC_CLK_TCK = 2
+  F_OK                =  0
+  R_OK                =  4
+  W_OK                =  2
+  X_OK                =  1
+  SC_CLK_TCK          =  2
+  SC_NPROCESSORS_ONLN = 84
 
   fun access(x0 : Char*, x1 : Int) : Int
   fun chdir(x0 : Char*) : Int

diff --git a/src/lib_c/x86_64-linux-gnu/c/unistd.cr b/src/lib_c/x86_64-linux-gnu/c/unistd.cr
@@ -2,11 +2,12 @@ require "./sys/types"
 require "./stdint"
 
 lib LibC
-  F_OK       = 0
-  R_OK       = 4
-  W_OK       = 2
-  X_OK       = 1
-  SC_CLK_TCK = 2
+  F_OK                =  0
+  R_OK                =  4
+  W_OK                =  2
+  X_OK                =  1
+  SC_CLK_TCK          =  2
+  SC_NPROCESSORS_ONLN = 84
 
   fun access(name : Char*, type : Int) : Int
   fun chdir(path : Char*) : Int

diff --git a/src/lib_c/x86_64-linux-musl/c/unistd.cr b/src/lib_c/x86_64-linux-musl/c/unistd.cr
@@ -2,11 +2,12 @@ require "./sys/types"
 require "./stdint"
 
 lib LibC
-  F_OK       = 0
-  R_OK       = 4
-  W_OK       = 2
-  X_OK       = 1
-  SC_CLK_TCK = 2
+  F_OK                =  0
+  R_OK                =  4
+  W_OK                =  2
+  X_OK                =  1
+  SC_CLK_TCK          =  2
+  SC_NPROCESSORS_ONLN = 84
 
   fun access(x0 : Char*, x1 : Int) : Int
   fun chdir(x0 : Char*) : Int

diff --git a/src/lib_c/x86_64-macosx-darwin/c/unistd.cr b/src/lib_c/x86_64-macosx-darwin/c/unistd.cr
@@ -2,11 +2,12 @@ require "./sys/types"
 require "./stdint"
 
 lib LibC
-  F_OK       = 0
-  R_OK       = 1 << 2
-  W_OK       = 1 << 1
-  X_OK       = 1 << 0
-  SC_CLK_TCK = 3
+  F_OK                = 0
+  R_OK                = 1 << 2
+  W_OK                = 1 << 1
+  X_OK                = 1 << 0
+  SC_CLK_TCK          =  3
+  SC_NPROCESSORS_ONLN = 58
 
   fun access(x0 : Char*, x1 : Int) : Int
   fun chdir(x0 : Char*) : Int

diff --git a/src/lib_c/x86_64-portbld-freebsd/c/unistd.cr b/src/lib_c/x86_64-portbld-freebsd/c/unistd.cr
@@ -2,11 +2,12 @@ require "./sys/types"
 require "./stdint"
 
 lib LibC
-  F_OK       =    0
-  R_OK       = 0x04
-  W_OK       = 0x02
-  X_OK       = 0x01
-  SC_CLK_TCK =    3
+  F_OK                =    0
+  R_OK                = 0x04
+  W_OK                = 0x02
+  X_OK                = 0x01
+  SC_CLK_TCK          =    3
+  SC_NPROCESSORS_ONLN =   58
 
   fun access(x0 : Char*, x1 : Int) : Int
   fun chdir(x0 : Char*) : Int

diff --git a/src/system.cr b/src/system.cr
@@ -18,4 +18,13 @@ module System
       {len, len}
     end
   end
+
+  # Returns the number of logical processors available to the system.
+  #
+  # ```
+  # System.cpu_count # => 4
+  # ```
+  def self.cpu_count
+    LibC.sysconf(LibC::SC_NPROCESSORS_ONLN)
+  end
 end