1 files changed, 179 insertions, 0 deletions

diff --git a/daemon/Proc.cpp b/daemon/Proc.cpp
new file mode 100644
index 0000000..e0b9e22
--- /dev/null
+++ b/daemon/Proc.cpp
@@ -0,0 +1,179 @@
+/**
+ * Copyright (C) ARM Limited 2013-2014. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "Proc.h"
+
+#include <dirent.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "Buffer.h"
+#include "DynBuf.h"
+#include "Logging.h"
+
+struct ProcStat {
+        // From linux-dev/include/linux/sched.h
+#define TASK_COMM_LEN 16
+        // TASK_COMM_LEN may grow, so be ready for it to get larger
+        char comm[2*TASK_COMM_LEN];
+        long numThreads;
+};
+
+static bool readProcStat(ProcStat *const ps, const char *const pathname, DynBuf *const b) {
+        if (!b->read(pathname)) {
+                logg->logMessage("%s(%s:%i): DynBuf::read failed, likely because the thread exited", __FUNCTION__, __FILE__, __LINE__);
+                // This is not a fatal error - the thread just doesn't exist any more
+                return true;
+        }
+
+        char *comm = strchr(b->getBuf(), '(');
+        if (comm == NULL) {
+                logg->logMessage("%s(%s:%i): parsing stat failed", __FUNCTION__, __FILE__, __LINE__);
+                return false;
+        }
+        ++comm;
+        char *const str = strrchr(comm, ')');
+        if (str == NULL) {
+                logg->logMessage("%s(%s:%i): parsing stat failed", __FUNCTION__, __FILE__, __LINE__);
+                return false;
+        }
+        *str = '\0';
+        strncpy(ps->comm, comm, sizeof(ps->comm) - 1);
+        ps->comm[sizeof(ps->comm) - 1] = '\0';
+
+        const int count = sscanf(str + 2, " %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %ld", &ps->numThreads);
+        if (count != 1) {
+                logg->logMessage("%s(%s:%i): sscanf failed", __FUNCTION__, __FILE__, __LINE__);
+                return false;
+        }
+
+        return true;
+}
+
+static bool readProcTask(Buffer *const buffer, const int pid, const char *const image, DynBuf *const printb, DynBuf *const b) {
+        bool result = false;
+
+        if (!b->printf("/proc/%i/task", pid)) {
+                logg->logMessage("%s(%s:%i): DynBuf::printf failed", __FUNCTION__, __FILE__, __LINE__);
+                return result;
+        }
+        DIR *task = opendir(b->getBuf());
+        if (task == NULL) {
+                logg->logMessage("%s(%s:%i): opendir failed", __FUNCTION__, __FILE__, __LINE__);
+                return result;
+        }
+
+        struct dirent *dirent;
+        while ((dirent = readdir(task)) != NULL) {
+                char *endptr;
+                const int tid = strtol(dirent->d_name, &endptr, 10);
+                if (*endptr != '\0') {
+                        // Ignore task items that are not integers like ., etc...
+                        continue;
+                }
+
+                if (!printb->printf("/proc/%i/task/%i/stat", pid, tid)) {
+                        logg->logMessage("%s(%s:%i): DynBuf::printf failed", __FUNCTION__, __FILE__, __LINE__);
+                        goto fail;
+                }
+                ProcStat ps;
+                if (!readProcStat(&ps, printb->getBuf(), b)) {
+                        logg->logMessage("%s(%s:%i): readProcStat failed", __FUNCTION__, __FILE__, __LINE__);
+                        goto fail;
+                }
+
+                buffer->comm(pid, tid, image, ps.comm);
+        }
+
+        result = true;
+
+ fail:
+        closedir(task);
+
+        return result;
+}
+
+bool readProc(Buffer *const buffer, DynBuf *const printb, DynBuf *const b1, DynBuf *const b2, DynBuf *const b3) {
+        bool result = false;
+
+        DIR *proc = opendir("/proc");
+        if (proc == NULL) {
+                logg->logMessage("%s(%s:%i): opendir failed", __FUNCTION__, __FILE__, __LINE__);
+                return result;
+        }
+
+        struct dirent *dirent;
+        while ((dirent = readdir(proc)) != NULL) {
+                char *endptr;
+                const int pid = strtol(dirent->d_name, &endptr, 10);
+                if (*endptr != '\0') {
+                        // Ignore proc items that are not integers like ., cpuinfo, etc...
+                        continue;
+                }
+
+                if (!printb->printf("/proc/%i/stat", pid)) {
+                        logg->logMessage("%s(%s:%i): DynBuf::printf failed", __FUNCTION__, __FILE__, __LINE__);
+                        goto fail;
+                }
+                ProcStat ps;
+                if (!readProcStat(&ps, printb->getBuf(), b1)) {
+                        logg->logMessage("%s(%s:%i): readProcStat failed", __FUNCTION__, __FILE__, __LINE__);
+                        goto fail;
+                }
+
+                if (!printb->printf("/proc/%i/exe", pid)) {
+                        logg->logMessage("%s(%s:%i): DynBuf::printf failed", __FUNCTION__, __FILE__, __LINE__);
+                        goto fail;
+                }
+                const int err = b1->readlink(printb->getBuf());
+                const char *image;
+                if (err == 0) {
+                        image = strrchr(b1->getBuf(), '/');
+                        if (image == NULL) {
+                                image = b1->getBuf();
+                        } else {
+                                ++image;
+                        }
+                } else if (err == -ENOENT) {
+                        // readlink /proc/[pid]/exe returns ENOENT for kernel threads
+                        image = "\0";
+                } else {
+                        logg->logMessage("%s(%s:%i): DynBuf::readlink failed", __FUNCTION__, __FILE__, __LINE__);
+                        goto fail;
+                }
+
+                if (!printb->printf("/proc/%i/maps", pid)) {
+                        logg->logMessage("%s(%s:%i): DynBuf::printf failed", __FUNCTION__, __FILE__, __LINE__);
+                        goto fail;
+                }
+                if (!b2->read(printb->getBuf())) {
+                        logg->logMessage("%s(%s:%i): DynBuf::read failed, likely because the process exited", __FUNCTION__, __FILE__, __LINE__);
+                        // This is not a fatal error - the process just doesn't exist any more
+                        continue;
+                }
+
+                buffer->maps(pid, pid, b2->getBuf());
+                if (ps.numThreads <= 1) {
+                        buffer->comm(pid, pid, image, ps.comm);
+                } else {
+                        if (!readProcTask(buffer, pid, image, printb, b3)) {
+                                logg->logMessage("%s(%s:%i): readProcTask failed", __FUNCTION__, __FILE__, __LINE__);
+                                goto fail;
+                        }
+                }
+        }
+
+        result = true;
+
+ fail:
+        closedir(proc);
+
+        return result;
+}