simplify check if tool is available

8 files changed, 30 insertions, 36 deletions

diff --git a/src/luarocks/fetch/svn.lua b/src/luarocks/fetch/svn.lua
index b2ae59c9..b6618afc 100644
--- a/src/luarocks/fetch/svn.lua
+++ b/src/luarocks/fetch/svn.lua
@@ -20,7 +20,7 @@ function svn.get_sources(rockspec, extract, dest_dir)
    assert(type(dest_dir) == "string" or not dest_dir)
 
    local svn_cmd = rockspec.variables.SVN
-   local ok, err_msg = fs.is_tool_available(svn_cmd, "Subversion", "--version")
+   local ok, err_msg = fs.is_tool_available(svn_cmd, "Subversion")
    if not ok then
       return nil, err_msg
    end
diff --git a/src/luarocks/fs/freebsd.lua b/src/luarocks/fs/freebsd.lua
deleted file mode 100644
index f72faa29..00000000
--- a/src/luarocks/fs/freebsd.lua
+++ /dev/null
@@ -1,11 +0,0 @@
---- FreeBSD implementation of filesystem and platform abstractions.
-local freebsd = {}
-
-local fs = require("luarocks.fs")
-
-function freebsd.init()
-   fs.set_tool_available("zip", true)
-   fs.set_tool_available("unzip", true)
-end
-
-return freebsd
diff --git a/src/luarocks/fs/lua.lua b/src/luarocks/fs/lua.lua
index 6bd80485..2619d136 100644
--- a/src/luarocks/fs/lua.lua
+++ b/src/luarocks/fs/lua.lua
@@ -114,19 +114,16 @@ end
 -- The tool is executed using a flag, usually just to ask its version.
 -- @param tool_cmd string: The command to be used to check the tool's presence (e.g. hg in case of Mercurial)
 -- @param tool_name string: The actual name of the tool (e.g. Mercurial)
--- @param arg string: The flag to pass to the tool. '--version' by default.
-function fs_lua.is_tool_available(tool_cmd, tool_name, arg)
+function fs_lua.is_tool_available(tool_cmd, tool_name)
    assert(type(tool_cmd) == "string")
    assert(type(tool_name) == "string")
 
-   arg = arg or "--version"
-   assert(type(arg) == "string")
-
    local ok
    if tool_available_cache[tool_name] ~= nil then
       ok = tool_available_cache[tool_name]
    else
-      ok = fs.execute_quiet(tool_cmd, arg)
+      local tool_cmd_no_args = tool_cmd:gsub(" .*", "")
+      ok = fs.search_in_path(tool_cmd_no_args)
       tool_available_cache[tool_name] = (ok == true)
    end
 
diff --git a/src/luarocks/fs/netbsd.lua b/src/luarocks/fs/netbsd.lua
deleted file mode 100644
index b9610339..00000000
--- a/src/luarocks/fs/netbsd.lua
+++ /dev/null
@@ -1,14 +0,0 @@
---- NetBSD implementation of filesystem and platform abstractions.
-local netbsd = {}
-
-local fs = require("luarocks.fs")
-
-function netbsd.init()
-    local uz=io.open("/usr/bin/unzip", "r")
-    if uz ~= nil then 
-        io.close(uz) 
-        fs.set_tool_available("unzip", true)
-    end
-end
-
-return netbsd
diff --git a/src/luarocks/fs/tools.lua b/src/luarocks/fs/tools.lua
index 0a154794..5c317f65 100644
--- a/src/luarocks/fs/tools.lua
+++ b/src/luarocks/fs/tools.lua
@@ -22,8 +22,8 @@ do
       md5checker = {
          desc = "MD5 checker",
          { var = "MD5SUM", name = "md5sum" },
-         { var = "OPENSSL", name = "openssl", cmdarg = "md5", checkarg = "version" },
-         { var = "MD5", name = "md5", checkarg = "-shello" },
+         { var = "OPENSSL", name = "openssl", cmdarg = "md5" },
+         { var = "MD5", name = "md5" },
       },
    }
 
@@ -33,7 +33,7 @@ do
       if not tool then
          for _, opt in ipairs(tool_options[tooltype]) do
             table.insert(names, opt.name)
-            if fs.is_tool_available(vars[opt.var], opt.name, opt.checkarg) then
+            if fs.is_tool_available(vars[opt.var], opt.name) then
                tool = opt
                tool_cache[tooltype] = opt
                break
diff --git a/src/luarocks/fs/unix.lua b/src/luarocks/fs/unix.lua
index 0065753e..28189089 100644
--- a/src/luarocks/fs/unix.lua
+++ b/src/luarocks/fs/unix.lua
@@ -234,4 +234,15 @@ function unix.system_cache_dir()
    return dir.path(fs.system_temp_dir(), "cache")
 end
 
+function unix.search_in_path(program)
+   for d in (os.getenv("PATH") or ""):gmatch("([^:]+)") do
+      local fd = io.open(dir.path(d, program), "r")
+      if fd then
+         fd:close()
+         return true, d
+      end
+   end
+   return false
+end
+
 return unix
diff --git a/src/luarocks/fs/unix/tools.lua b/src/luarocks/fs/unix/tools.lua
index d36d407d..f0c0a05c 100644
--- a/src/luarocks/fs/unix/tools.lua
+++ b/src/luarocks/fs/unix/tools.lua
@@ -141,7 +141,7 @@ end
 -- @return boolean: true on success, nil and error message on failure.
 function tools.unzip(zipfile)
    assert(zipfile)
-   local ok, err = fs.is_tool_available(vars.UNZIP, "unzip", "--help")
+   local ok, err = fs.is_tool_available(vars.UNZIP, "unzip")
    if not ok then
       return nil, err
    end
diff --git a/src/luarocks/fs/win32.lua b/src/luarocks/fs/win32.lua
index a3f42df7..6c49f447 100644
--- a/src/luarocks/fs/win32.lua
+++ b/src/luarocks/fs/win32.lua
@@ -363,4 +363,15 @@ function win32.system_cache_dir()
    return dir.path(fs.system_temp_dir(), "cache")
 end
 
+function win32.search_in_path(program)
+   for d in (os.getenv("PATH") or ""):gmatch("([^;]+)") do
+      local fd = io.open(dir.path(d, program .. ".exe"), "r")
+      if fd then
+         fd:close()
+         return true, d
+      end
+   end
+   return false
+end
+
 return win32