Merge pull request #108 from anomen-s/issue-23-r

Add -l option to show full command line (fixes #23)

doc/nethogs.8

@@ -15,6 +15,7 @@ nethogs \- Net top tool grouping bandwidth per process
 .RB [ "\-p" ]
 .RB [ "\-a" ]
 .RB [ "\-s" ]
+.RB [ "\-l" ]
 .RI [device(s)]
 .SH DESCRIPTION
 NetHogs is a small 'net top' tool. Instead of breaking the traffic down per protocol or per subnet, like most such tools do, it groups bandwidth by process - and does not rely on a special kernel module to be loaded. So if there's suddenly a lot of network traffic, you can fire up NetHogs and immediately see which PID is causing this, and if it's some kind of spinning process, kill it. 
@@ -47,6 +48,9 @@ limit number of refreshes
 .TP
 \fB-s\fP
 sort by traffic sent
+.TP
+\fB-l\fP
+display command line
 .PP
 .I device(s)
 to monitor. By default eth0 is being used
@@ -56,8 +60,11 @@ to monitor. By default eth0 is being used
 m
 cycle between display modes (KB/s, KB, B, MB)
 .TP
+l
+display command line
+.TP
 r
-sort by 'received' 
+sort by 'received'
 .TP
 s
 sort by 'sent'

src/cui.cpp

@@ -45,6 +45,7 @@ extern Process *unknownip;
 extern bool sortRecv;
 
 extern int viewMode;
+extern bool showcommandline;
 
 extern unsigned refreshlimit;
 extern unsigned refreshcount;
@@ -64,11 +65,12 @@ const char *COLUMN_FORMAT_RECEIVED = "%11.3f";
 
 class Line {
 public:
-  Line(const char *name, double n_recv_value, double n_sent_value, pid_t pid,
+  Line(const char *name, const char *cmdline, double n_recv_value,
-       uid_t uid, const char *n_devicename) {
+       double n_sent_value, pid_t pid, uid_t uid, const char *n_devicename) {
     assert(pid >= 0);
     assert(pid <= PID_MAX);
     m_name = name;
+    m_cmdline = cmdline;
     sent_value = n_sent_value;
     recv_value = n_recv_value;
     devicename = n_devicename;
@@ -85,6 +87,7 @@ public:
 
 private:
   const char *m_name;
+  const char *m_cmdline;
   const char *devicename;
   pid_t m_pid;
   uid_t m_uid;
@@ -118,23 +121,6 @@ std::string uid2username(uid_t uid) {
     return std::string(pwd->pw_name);
 }
 
-/**
- * Render the provided text at the specified location, truncating if the length
- * of the text exceeds a maximum. If the
- * text must be truncated, the string ".." will be rendered, followed by max_len
- * - 2 characters of the provided text.
- */
-static void mvaddstr_truncate_leading(int row, int col, const char *str,
-                                      std::size_t str_len,
-                                      std::size_t max_len) {
-  if (str_len < max_len) {
-    mvaddstr(row, col, str);
-  } else {
-    mvaddstr(row, col, "..");
-    addnstr(str + 2, max_len - 2);
-  }
-}
-
 /**
  * Render the provided text at the specified location, truncating if the length
  * of the text exceeds a maximum. If the
@@ -152,6 +138,43 @@ static void mvaddstr_truncate_trailing(int row, int col, const char *str,
   }
 }
 
+/**
+ * Render the provided progname and cmdline at the specified location,
+ * truncating if the length of the values exceeds a maximum.
+ * If the text must be truncated, the text will be rendered up to max_len - 2
+ * characters and then ".." will be rendered.
+ * cmdline is truncated first and then progname.
+ */
+static void mvaddstr_truncate_cmdline(int row, int col, const char *progname,
+                                      const char *cmdline,
+                                      std::size_t max_len) {
+  std::size_t proglen = strlen(progname);
+  std::size_t max_cmdlen;
+
+  if (proglen > max_len) {
+    mvaddnstr(row, col, progname, max_len - 2);
+    addstr("..");
+    max_cmdlen = 0;
+  } else {
+    mvaddstr(row, col, progname);
+    max_cmdlen = max_len - proglen - 1;
+  }
+
+  if (showcommandline && cmdline) {
+
+    std::size_t cmdlinelen = strlen(cmdline);
+
+    if ((cmdlinelen + 1) > max_cmdlen) {
+      if (max_cmdlen >= 3) {
+        mvaddnstr(row, col + proglen + 1, cmdline, max_cmdlen - 3);
+        addstr("..");
+      }
+    } else {
+      mvaddstr(row, col + proglen + 1, cmdline);
+    }
+  }
+}
+
 void Line::show(int row, unsigned int proglen) {
   assert(m_pid >= 0);
   assert(m_pid <= PID_MAX);
@@ -175,7 +198,7 @@ void Line::show(int row, unsigned int proglen) {
   mvaddstr_truncate_trailing(row, column_offset_user, username.c_str(),
                              username.size(), COLUMN_WIDTH_USER);
 
-  mvaddstr_truncate_leading(row, column_offset_program, m_name, strlen(m_name),
+  mvaddstr_truncate_cmdline(row, column_offset_program, m_name, m_cmdline,
                             proglen);
 
   mvaddstr(row, column_offset_dev, devicename);
@@ -195,8 +218,10 @@ void Line::show(int row, unsigned int proglen) {
 }
 
 void Line::log() {
-  std::cout << m_name << '/' << m_pid << '/' << m_uid << "\t" << sent_value
+  std::cout << m_name;
-            << "\t" << recv_value << std::endl;
+  if (showcommandline && m_cmdline)
+    std::cout << ' ' << m_cmdline;
+  std::cout << '/' << m_pid << '/' << m_uid << "\t" << sent_value << "\t" << recv_value << std::endl;
 }
 
 int GreatestFirst(const void *ma, const void *mb) {
@@ -258,6 +283,10 @@ void ui_tick() {
     /* sort on 'received' */
     sortRecv = true;
     break;
+  case 'l':
+    /* show cmdline' */
+    showcommandline = !showcommandline;
+    break;
   case 'm':
     /* switch mode: total vs kb/s */
     viewMode = (viewMode + 1) % VIEWMODE_COUNT;
@@ -386,9 +415,9 @@ void do_refresh() {
     assert(curproc->getVal()->pid >= 0);
     assert(n < nproc);
 
-    lines[n] =
+    lines[n] = new Line(curproc->getVal()->name, curproc->getVal()->cmdline,
-      new Line(curproc->getVal()->name, value_recv, value_sent,
+                        value_recv, value_sent, curproc->getVal()->pid, uid,
-               curproc->getVal()->pid, uid, curproc->getVal()->devicename);
+                        curproc->getVal()->devicename);
     curproc = curproc->next;
     n++;
   }

src/inode2prog.cpp

@@ -116,12 +116,32 @@ static std::string read_file(const char *filepath) {
   return contents;
 }
 
-std::string getprogname(pid_t pid) {
+std::string getcmdline(pid_t pid) {
   const int maxfilenamelen = 14 + MAX_PID_LENGTH + 1;
   char filename[maxfilenamelen];
 
   std::snprintf(filename, maxfilenamelen, "/proc/%d/cmdline", pid);
-  return read_file(filename);
+
+  bool replace_null = false;
+  std::string cmdline = read_file(filename);
+
+  // join parameters, keep prgname separate, don't overwrite trailing null
+  for (size_t idx = 0; idx < (cmdline.length() - 1); idx++) {
+    if (cmdline[idx] == 0x00) {
+      if (replace_null) {
+        cmdline[idx] = ' ';
+      }
+      replace_null = true;
+    }
+  }
+
+  if (cmdline.length() == 0 || (cmdline[cmdline.length() - 1] != 0x00)) {
+    // invalid content of cmdline file. Add null char to allow further
+    // processing.
+    cmdline.append("\0");
+  }
+
+  return cmdline;
 }
 
 void setnode(unsigned long inode, pid_t pid) {
@@ -131,7 +151,7 @@ void setnode(unsigned long inode, pid_t pid) {
     prg_node *newnode = new prg_node;
     newnode->inode = inode;
     newnode->pid = pid;
-    newnode->name = getprogname(pid);
+    newnode->cmdline = getcmdline(pid);
 
     inodeproc[inode] = newnode;
     delete current_value;

src/inode2prog.h

@@ -31,7 +31,7 @@
 struct prg_node {
   long inode;
   pid_t pid;
-  std::string name;
+  std::string cmdline;
 };
 
 struct prg_node *findPID(unsigned long inode);

src/main.cpp

@@ -27,7 +27,7 @@ static void help(bool iserror) {
   // output << "usage: nethogs [-V] [-b] [-d seconds] [-t] [-p] [-f (eth|ppp))]
   // [device [device [device ...]]]\n";
   output << "usage: nethogs [-V] [-h] [-b] [-d seconds] [-v mode] [-c count] "
-            "[-t] [-p] [-s] [-a] [device [device [device ...]]]\n";
+            "[-t] [-p] [-s] [-a] [-l] [device [device [device ...]]]\n";
   output << "		-V : prints version.\n";
   output << "		-h : prints this help.\n";
   output << "		-b : bughunt mode - implies tracemode.\n";
@@ -41,6 +41,7 @@ static void help(bool iserror) {
   // eth.\n";
   output << "		-p : sniff in promiscious mode (not recommended).\n";
   output << "		-s : sort output by sent column.\n";
+  output << "		-l : display command line.\n";
   output << "		-a : monitor all devices, even loopback/stopped ones.\n";
   output << "		device : device(s) to monitor. default is all "
             "interfaces up and running excluding loopback\n";
@@ -49,6 +50,7 @@ static void help(bool iserror) {
   output << " q: quit\n";
   output << " s: sort by SENT traffic\n";
   output << " r: sort by RECEIVE traffic\n";
+  output << " l: display command line\n";
   output << " m: switch between total (KB, B, MB) and KB/s mode\n";
 }
 
@@ -133,7 +135,7 @@ int main(int argc, char **argv) {
   bool all = false;
 
   int opt;
-  while ((opt = getopt(argc, argv, "Vhbtpsd:v:c:a")) != -1) {
+  while ((opt = getopt(argc, argv, "Vhbtpsd:v:c:la")) != -1) {
     switch (opt) {
     case 'V':
       versiondisplay();
@@ -163,6 +165,9 @@ int main(int argc, char **argv) {
     case 'c':
       refreshlimit = atoi(optarg);
       break;
+    case 'l':
+      showcommandline = true;
+      break;
     case 'a':
       all = true;
       break;

src/nethogs.cpp

@@ -59,6 +59,7 @@ bool tracemode = false;
 bool bughuntmode = false;
 // sort on sent or received?
 bool sortRecv = true;
+bool showcommandline = false;
 // viewMode: kb/s or total
 int viewMode = VIEWMODE_KBPS;
 const char version[] = " version " VERSION;

src/process.cpp

@@ -225,7 +225,11 @@ Process *getProcess(unsigned long inode, const char *devicename) {
   if (proc != NULL)
     return proc;
 
-  Process *newproc = new Process(inode, devicename, node->name.c_str());
+  // extract program name and command line from data read from cmdline file
+  const char *prgname = node->cmdline.c_str();
+  const char *cmdline = prgname + strlen(prgname) + 1;
+
+  Process *newproc = new Process(inode, devicename, prgname, cmdline);
   newproc->pid = node->pid;
 
   char procdir[100];

src/process.h

@@ -57,7 +57,7 @@ public:
   /* the process makes a copy of the name. the device name needs to be stable.
    */
   Process(const unsigned long m_inode, const char *m_devicename,
-          const char *m_name = NULL)
+          const char *m_name = NULL, const char *m_cmdline = NULL)
       : inode(m_inode) {
     // std::cout << "ARN: Process created with dev " << m_devicename <<
     // std::endl;
@@ -69,6 +69,11 @@ public:
     else
       name = strdup(m_name);
 
+    if (m_cmdline == NULL)
+      cmdline = NULL;
+    else
+      cmdline = strdup(m_cmdline);
+
     devicename = m_devicename;
     connections = NULL;
     pid = 0;
@@ -78,6 +83,7 @@ public:
 
   ~Process() {
     free(name);
+    free(cmdline);
     if (DEBUG)
       std::cout << "PROC: Process deleted at " << this << std::endl;
   }
@@ -90,6 +96,7 @@ public:
   void gettotalb(float *recvd, float *sent);
 
   char *name;
+  char *cmdline;
   const char *devicename;
   int pid;