From a8bee35697e9d97401f24c8b1c1c8a2869546baf Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop@gmail.com>
Date: Tue, 15 Mar 2016 23:02:05 -0400
Subject: [PATCH] make SvnRunner usable as a class

---
 src/SvnRunner.cc | 67 +++++++++++++++++++++++++++---------------------
 src/SvnRunner.h  | 13 +++++++++-
 src/svi.cc       | 10 +++++++-
 3 files changed, 59 insertions(+), 31 deletions(-)

diff --git a/src/SvnRunner.cc b/src/SvnRunner.cc
index de07219..094773a 100644
--- a/src/SvnRunner.cc
+++ b/src/SvnRunner.cc
@@ -1,12 +1,11 @@
 #include "SvnRunner.h"
-#include <stdio.h>
-#include <unistd.h>
 #include <stdlib.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 
-void SvnRunner::exec_svn(std::vector<std::string> arguments)
+SvnRunner::SvnRunner(std::vector<std::string> arguments)
 {
+    m_pid = 0;
     int fd[2];
     int pipe_rc = pipe(fd);
     if (pipe_rc == -1)
@@ -14,13 +13,13 @@ void SvnRunner::exec_svn(std::vector<std::string> arguments)
         perror("pipe");
         return;
     }
-    pid_t pid = fork();
-    if (pid == -1)
+    m_pid = fork();
+    if (m_pid == -1)
     {
         perror("fork");
         return;
     }
-    if (pid == 0)
+    if (m_pid == 0)
     {
         close(fd[0]);
         int dup2_rc = dup2(fd[1], STDOUT_FILENO);
@@ -46,28 +45,38 @@ void SvnRunner::exec_svn(std::vector<std::string> arguments)
     else
     {
         close(fd[1]);
-        size_t n = 100;
-        char * line = (char *)malloc(n);
-        FILE * in = fdopen(fd[0], "r");
-        ssize_t getline_rc;
-        for (;;)
-        {
-            getline_rc = getline(&line, &n, in);
-            if (getline_rc == -1)
-                break;
-            printf("Got >%s<\n", line);
-        }
-        fclose(in);
-        int status;
-        int waitpid_rc = waitpid(pid, &status, 0);
-        if (waitpid_rc == -1)
-        {
-            perror("waitpid");
-        }
-        if (WEXITSTATUS(status) != 0)
-        {
-            fprintf(stderr, "Warning: svn exit status = %d\n", WEXITSTATUS(status));
-        }
-        free(line);
+        m_n = 100;
+        m_line = (char *)malloc(m_n);
+        m_svn_fh = fdopen(fd[0], "r");
+    }
+}
+
+const char * SvnRunner::get_line()
+{
+    if (m_pid > 0)
+    {
+        ssize_t getline_rc = getline(&m_line, &m_n, m_svn_fh);
+        if (getline_rc == -1)
+        {
+            fclose(m_svn_fh);
+            int status;
+            int waitpid_rc = waitpid(m_pid, &status, 0);
+            if (waitpid_rc == -1)
+            {
+                perror("waitpid");
+            }
+            m_status = WEXITSTATUS(status);
+            free(m_line);
+            m_pid = 0;
+            return NULL;
+        }
+        else
+        {
+            return m_line;
+        }
+    }
+    else
+    {
+        return NULL;
     }
 }
diff --git a/src/SvnRunner.h b/src/SvnRunner.h
index a36d180..c5152d1 100644
--- a/src/SvnRunner.h
+++ b/src/SvnRunner.h
@@ -1,8 +1,19 @@
 #include <string>
 #include <vector>
+#include <unistd.h>
+#include <stdio.h>
 
 class SvnRunner
 {
 public:
-    static void exec_svn(std::vector<std::string> arguments);
+    SvnRunner(std::vector<std::string> arguments);
+    const char * get_line();
+    int status() { return m_status; }
+
+protected:
+    char * m_line;
+    size_t m_n;
+    pid_t m_pid;
+    FILE * m_svn_fh;
+    int m_status;
 };
diff --git a/src/svi.cc b/src/svi.cc
index 402acea..3557e47 100644
--- a/src/svi.cc
+++ b/src/svi.cc
@@ -6,5 +6,13 @@ using namespace std;
 int main(int argc, char * argv[])
 {
     cout << "Hello there." << endl;
-    SvnRunner::exec_svn({"ls"});
+    SvnRunner runner({"ls"});
+    for(;;)
+    {
+        const char * line = runner.get_line();
+        if (line == NULL)
+            break;
+        fprintf(stdout, ">> %s", line);
+    }
+    fprintf(stdout, "Exit status: %d\n", runner.status());
 }