Start by linking processes together in a family tree

src/process.h

@@ -5,8 +5,11 @@
 
 typedef struct st_process {
     // For our own purposes
-    struct st_process *next;
-    struct st_process *prev;
+    struct st_process *next;    // next process in order we read them
+    struct st_process *prev;    // previous process read
+    struct st_process *parent;  // parent process
+    struct st_process *child;   // pointer to first child
+    struct st_process *sibling; // pointer to next sibling
     uint32_t flags;
     char cpuset[128];
     int tgid;
@@ -14,17 +17,22 @@ typedef struct st_process {
     int lxc;
     int pid;
     int ppid;
-    int level;
     char label[128];
     // statistics - each outputs 1 line per process
+    int level;
     int iskernel;
     uint64_t cpuTime;
-    uint64_t childCpuTime;
     uint64_t nThreads;
     uint64_t resident;
     uint64_t swap;
     uint64_t written;
     uint64_t read;
+
+    uint64_t childCpuTime;
+    uint64_t childMemory;
+    uint64_t childSwap;
+    uint64_t childRead;
+    uint64_t childWrite;
 } Process;
 
 #endif

src/server.c

@@ -90,6 +90,37 @@ int parseIOFile(Process *proc, char *filedata) {
   return 0;
 }
 
+void linkFamily(Process *head) {
+  int orphans = 1;
+
+  while (orphans) {
+    orphans = 0;
+    Process *current = head;
+    // while on an actual process node, and it doesn't have a parent link, and should have a parent link
+    while (current != NULL && (current->parent != NULL || current->ppid <= 0)) current = current->next;
+    if (current == NULL) break;
+    orphans = 1;
+    
+    Process *parent = head;
+    while (parent != NULL && parent->pid != current->ppid) parent = parent->next;
+    if (parent == NULL) {
+      printf("Found orphan process: %d\n", current->pid);
+      current->ppid = -1;
+      continue;
+    }
+
+    // We have a parent and a child ready to be united
+    current->parent = parent;
+    Process **placement = &(parent->child);
+    while ((*placement) != NULL) placement = &((*placement)->sibling);
+    *placement = current;
+  }
+}
+
+void aggregateStats(Process *head) {
+
+}
+
 char *readProcesses(char *procdir) {
   int len;
   struct dirent *pDirent;
@@ -172,6 +203,8 @@ char *readProcesses(char *procdir) {
   free(cur->next);
   cur->next = NULL;
 
+  linkFamily(head);
+
   int clocks = sysconf(_SC_CLK_TCK);
   char *output = malloc(8 * 1024 * 1024);
   char *ptr = output;
@@ -180,8 +213,8 @@ char *readProcesses(char *procdir) {
   while (cur != NULL) {
     // create process descriptor
     sprintf(buffer,
-            "pid=\"%d\",ppid=\"%d\",label=\"%s\",lxc=\"%d\",level=\"%d\"",
-            cur->pid, cur->ppid, cur->label, cur->lxc, cur->level);
+            "pid=\"%d\",ppid=\"%d\",label=\"%s\",lxc=\"%d\"",
+            cur->pid, cur->ppid, cur->label, cur->lxc);
     ptr += sprintf(ptr, "process_cpu_time_seconds{%s} %f\n", buffer, (double) cur->cpuTime / clocks);
     ptr += sprintf(ptr, "process_child_cpu_time_seconds{%s} %f\n", buffer,(double) cur->childCpuTime / clocks);
     ptr += sprintf(ptr, "process_num_threads{%s} %llu\n", buffer, cur->nThreads);
@@ -190,6 +223,7 @@ char *readProcesses(char *procdir) {
     ptr += sprintf(ptr, "process_fileio_bytes_written{%s} %llu\n", buffer, cur->written);
     ptr += sprintf(ptr, "process_fileio_bytes_read{%s} %llu\n", buffer, cur->read);
     ptr += sprintf(ptr, "process_is_kernel_process{%s} %d\n", buffer, cur->iskernel);
+    ptr += sprintf(ptr, "process_tree_depth{%s} %d\n", buffer, cur->level);
     // free and proceed
     Process *prev = cur;
     cur = cur->next;
@@ -248,9 +282,14 @@ void handle_client(int client_socket) {
     int amt = length - total_sent;
     int sent = send(client_socket, data + total_sent, amt, 0);
     printf("Tried sending %d actually sent %d\n", amt, sent);
+    if (sent == -1) {
+      printf("Failed to complete response\n");
+      goto closeConnection;
+    }
     total_sent += sent;
   }
 
+closeConnection:
   printf("Closing connection\n");
   // Close the client socket
   shutdown(client_socket, SHUT_WR);
@@ -267,6 +306,7 @@ int main(int argc, char *argv[]) {
     char *buf = readProcesses("/proc");
     if (buf == NULL) return 4;
     printf(buf);
+    free(buf);
     return 0;
 
   } else {