1 files changed, 85 insertions, 0 deletions
diff --git a/src/shell_manager.cc b/src/shell_manager.cc
new file mode 100644
index 00000000..f750ab05
--- /dev/null
+++ b/src/shell_manager.cc
@@ -0,0 +1,85 @@
+#include "shell_manager.hh"
+
+#include <cstring>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+namespace Kakoune
+{
+
+ShellManager::ShellManager()
+   : m_regex(LR"(\$\{kak_([a-z0-9_]+)[^}]*\}|\$kak_([a-z0-9_]+))")
+{
+}
+
+String ShellManager::eval(const String& cmdline, const Context& context)
+{
+    int write_pipe[2];
+    int read_pipe[2];
+
+    pipe(write_pipe);
+    pipe(read_pipe);
+
+    String output;
+    if (pid_t pid = fork())
+    {
+        close(write_pipe[0]);
+        close(read_pipe[1]);
+        close(write_pipe[1]);
+
+        char buffer[1024];
+        while (size_t size = read(read_pipe[0], buffer, 1024))
+        {
+            if (size == -1)
+                break;
+            output += String(buffer, buffer+size);
+        }
+        close(read_pipe[0]);
+        waitpid(pid, NULL, 0);
+    }
+    else
+    {
+        close(write_pipe[1]);
+        close(read_pipe[0]);
+
+        dup2(read_pipe[1], 1);
+        dup2(write_pipe[0], 0);
+
+        boost::regex_iterator<String::iterator> it(cmdline.begin(), cmdline.end(), m_regex);
+        boost::regex_iterator<String::iterator> end;
+
+        while (it != end)
+        {
+            auto& match = *it;
+
+            String name;
+            if (match[1].matched)
+                name = String(match[1].first, match[1].second);
+            else if (match[2].matched)
+                name = String(match[2].first, match[2].second);
+            else
+                assert(false);
+            assert(name.length() > 0);
+
+            auto env_var = m_env_vars.find(name);
+            if (env_var != m_env_vars.end())
+            {
+                String value = env_var->second(context);
+                setenv(("kak_" + name).c_str(), value.c_str(), 1);
+            }
+
+            ++it;
+        }
+
+        execlp("sh", "sh", "-c", cmdline.c_str(), NULL);
+    }
+    return output;
+}
+
+void ShellManager::register_env_var(const String& name,
+                                    EnvVarRetriever retriever)
+{
+    m_env_vars[name] = std::move(retriever);
+}
+
+}