From 635ca31754ae734b0c540ac5600d58ae55cd4237 Mon Sep 17 00:00:00 2001
From: Felipe Leme <felipeal@google.com>
Date: Tue, 5 Jan 2016 14:23:02 -0800
Subject: [PATCH] Include mount info on zipped bugreport.

BUG: 7280247
Change-Id: Iae2a7881c11564c8dbd3641f5ee5ab72c181da2a
---
 cmds/dumpstate/dumpstate.cpp | 44 ++++++++++++++++++++++++++++++++++++++++++--
 cmds/dumpstate/utils.cpp     |  2 +-
 2 files changed, 43 insertions(+), 3 deletions(-)

diff --git a/cmds/dumpstate/dumpstate.cpp b/cmds/dumpstate/dumpstate.cpp
index 296dad4428..8dcca3484b 100644
--- a/cmds/dumpstate/dumpstate.cpp
+++ b/cmds/dumpstate/dumpstate.cpp
@@ -21,6 +21,7 @@
 #include <limits.h>
 #include <memory>
 #include <regex>
+#include <set>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -56,6 +57,9 @@ static const char *dump_traces_path = NULL;
 static char build_type[PROPERTY_VALUE_MAX];
 static time_t now;
 static std::unique_ptr<ZipWriter> zip_writer;
+static std::set<std::string> mount_points;
+void add_mountinfo();
+static bool add_zip_entry(const std::string& entry_name, const std::string& entry_path);
 
 #define PSTORE_LAST_KMSG "/sys/fs/pstore/console-ramoops"
 
@@ -96,6 +100,41 @@ static void get_tombstone_fds(tombstone_data_t data[NUM_TOMBSTONES]) {
     }
 }
 
+// for_each_pid() callback to get mount info about a process.
+void do_mountinfo(int pid, const char *name) {
+    char path[PATH_MAX];
+
+    // Gets the the content of the /proc/PID/ns/mnt link, so only unique mount points
+    // are added.
+    sprintf(path, "/proc/%d/ns/mnt", pid);
+    char linkname[PATH_MAX];
+    ssize_t r = readlink(path, linkname, PATH_MAX);
+    if (r == -1) {
+        ALOGE("Unable to read link for %s: %s\n", path, strerror(errno));
+        return;
+    }
+    linkname[r] = '\0';
+
+    if (mount_points.find(linkname) == mount_points.end()) {
+        // First time this mount point was found: add it
+        sprintf(path, "/proc/%d/mountinfo", pid);
+        if (add_zip_entry(ZIP_ROOT_DIR + path, path)) {
+            mount_points.insert(linkname);
+        } else {
+            ALOGE("Unable to add mountinfo %s to zip file\n", path);
+        }
+    }
+}
+
+void add_mountinfo() {
+    if (!zip_writer) return;
+    const char *title = "MOUNT INFO";
+    mount_points.clear();
+    DurationReporter duration_reporter(title);
+    for_each_pid(do_mountinfo, NULL);
+    printf("%s: %d entries added to zip file\n", title, mount_points.size());
+}
+
 static void dump_dev_files(const char *title, const char *driverpath, const char *filename)
 {
     DIR *d;
@@ -811,7 +850,7 @@ int main(int argc, char *argv[]) {
     /* pointer to the actual path, be it zip or text */
     std::string path;
 
-    /* pointers to the zipped file file */
+    /* pointer to the zipped file */
     std::unique_ptr<FILE, int(*)(FILE*)> zip_file(NULL, fclose);
 
     /* redirect output if needed */
@@ -904,9 +943,10 @@ int main(int argc, char *argv[]) {
     /* collect stack traces from Dalvik and native processes (needs root) */
     dump_traces_path = dump_traces();
 
-    /* Get the tombstone fds and recovery files here while we are running as root. */
+    /* Get the tombstone fds, recovery files, and mount info here while we are running as root. */
     get_tombstone_fds(tombstone_data);
     add_dir(RECOVERY_DIR, true);
+    add_mountinfo();
 
     /* ensure we will keep capabilities when we drop root */
     if (prctl(PR_SET_KEEPCAPS, 1) < 0) {
diff --git a/cmds/dumpstate/utils.cpp b/cmds/dumpstate/utils.cpp
index 78bab819b3..e49d766f1e 100644
--- a/cmds/dumpstate/utils.cpp
+++ b/cmds/dumpstate/utils.cpp
@@ -114,7 +114,7 @@ static void __for_each_pid(void (*helper)(int, const char *, void *), const char
         return;
     }
 
-    printf("\n------ %s ------\n", header);
+    if (header) printf("\n------ %s ------\n", header);
     while ((de = readdir(d))) {
         int pid;
         int fd;
-- 
2.11.0