gecko-dev/xpcom/base/SystemMemoryReporter.cpp

819 строки
28 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/SystemMemoryReporter.h"
#include "mozilla/Attributes.h"
#include "mozilla/PodOperations.h"
#include "mozilla/Preferences.h"
#include "mozilla/TaggedAnonymousMemory.h"
#include "mozilla/unused.h"
#include "nsDataHashtable.h"
#include "nsIMemoryReporter.h"
#include "nsPrintfCString.h"
#include "nsString.h"
#include "nsTHashtable.h"
#include "nsHashKeys.h"
#include <dirent.h>
#include <inttypes.h>
#include <stdio.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <errno.h>
// This file implements a Linux-specific, system-wide memory reporter. It
// gathers all the useful memory measurements obtainable from the OS in a
// single place, giving a high-level view of memory consumption for the entire
// machine/device.
//
// Other memory reporters measure part of a single process's memory consumption.
// This reporter is different in that it measures memory consumption of many
// processes, and they end up in a single reports tree. This is a slight abuse
// of the memory reporting infrastructure, and therefore the results are given
// their own "process" called "System", which means they show up in about:memory
// in their own section, distinct from the per-process sections.
namespace mozilla {
namespace SystemMemoryReporter {
#if !defined(XP_LINUX)
#error "This won't work if we're not on Linux."
#endif
static bool
EndsWithLiteral(const nsCString& aHaystack, const char* aNeedle)
{
int32_t idx = aHaystack.RFind(aNeedle);
return idx != -1 && idx + strlen(aNeedle) == aHaystack.Length();
}
static void
GetDirname(const nsCString& aPath, nsACString& aOut)
{
int32_t idx = aPath.RFind("/");
if (idx == -1) {
aOut.Truncate();
} else {
aOut.Assign(Substring(aPath, 0, idx));
}
}
static void
GetBasename(const nsCString& aPath, nsACString& aOut)
{
nsCString out;
int32_t idx = aPath.RFind("/");
if (idx == -1) {
out.Assign(aPath);
} else {
out.Assign(Substring(aPath, idx + 1));
}
// On Android, some entries in /dev/ashmem end with "(deleted)" (e.g.
// "/dev/ashmem/libxul.so(deleted)"). We don't care about this modifier, so
// cut it off when getting the entry's basename.
if (EndsWithLiteral(out, "(deleted)")) {
out.Assign(Substring(out, 0, out.RFind("(deleted)")));
}
out.StripChars(" ");
aOut.Assign(out);
}
static bool
IsNumeric(const char* aStr)
{
MOZ_ASSERT(*aStr); // shouldn't see empty strings
while (*aStr) {
if (!isdigit(*aStr)) {
return false;
}
++aStr;
}
return true;
}
static bool
IsAnonymous(const nsACString& aName)
{
// Recent kernels (e.g. 3.5) have multiple [stack:nnnn] entries, where |nnnn|
// is a thread ID. However, [stack:nnnn] entries count both stack memory
// *and* anonymous memory because the kernel only knows about the start of
// each thread stack, not its end. So we treat such entries as anonymous
// memory instead of stack. This is consistent with older kernels that don't
// even show [stack:nnnn] entries.
return aName.IsEmpty() ||
StringBeginsWith(aName, NS_LITERAL_CSTRING("[stack:"));
}
class SystemReporter MOZ_FINAL : public nsIMemoryReporter
{
public:
NS_DECL_THREADSAFE_ISUPPORTS
#define REPORT_WITH_CLEANUP(_path, _units, _amount, _desc, _cleanup) \
do { \
size_t amount = _amount; /* evaluate _amount only once */ \
if (amount > 0) { \
nsresult rv; \
rv = aHandleReport->Callback(NS_LITERAL_CSTRING("System"), _path, \
KIND_NONHEAP, _units, amount, _desc, \
aData); \
if (NS_WARN_IF(NS_FAILED(rv))) { \
_cleanup; \
return rv; \
} \
} \
} while (0)
#define REPORT(_path, _amount, _desc) \
REPORT_WITH_CLEANUP(_path, UNITS_BYTES, _amount, _desc, (void)0)
NS_IMETHOD CollectReports(nsIHandleReportCallback* aHandleReport,
nsISupports* aData, bool aAnonymize)
{
// There is lots of privacy-sensitive data in /proc. Just skip this
// reporter entirely when anonymization is required.
if (aAnonymize)
return NS_OK;
if (!Preferences::GetBool("memory.system_memory_reporter")) {
return NS_OK;
}
// Read relevant fields from /proc/meminfo.
int64_t memTotal = 0, memFree = 0;
nsresult rv = ReadMemInfo(&memTotal, &memFree);
// Collect per-process reports from /proc/<pid>/smaps.
int64_t totalPss = 0;
rv = CollectProcessReports(aHandleReport, aData, &totalPss);
NS_ENSURE_SUCCESS(rv, rv);
// Report the non-process numbers.
int64_t other = memTotal - memFree - totalPss;
REPORT(NS_LITERAL_CSTRING("mem/other"), other, NS_LITERAL_CSTRING(
"Memory which is neither owned by any user-space process nor free. Note that "
"this includes memory holding cached files from the disk which can be "
"reclaimed by the OS at any time."));
REPORT(NS_LITERAL_CSTRING("mem/free"), memFree, NS_LITERAL_CSTRING(
"Memory which is free and not being used for any purpose."));
// Report reserved memory not included in memTotal.
rv = CollectPmemReports(aHandleReport, aData);
NS_ENSURE_SUCCESS(rv, rv);
// Report zram usage statistics.
rv = CollectZramReports(aHandleReport, aData);
NS_ENSURE_SUCCESS(rv, rv);
return rv;
}
private:
// These are the cross-cutting measurements across all processes.
class ProcessSizes
{
public:
void Add(const nsACString &aKey, size_t aSize)
{
mTagged.Put(aKey, mTagged.Get(aKey) + aSize);
}
void Report(nsIHandleReportCallback *aHandleReport, nsISupports *aData)
{
EnumArgs env = { aHandleReport, aData };
mTagged.EnumerateRead(ReportSizes, &env);
}
private:
nsDataHashtable<nsCStringHashKey, size_t> mTagged;
struct EnumArgs {
nsIHandleReportCallback* mHandleReport;
nsISupports* mData;
};
static PLDHashOperator ReportSizes(nsCStringHashKey::KeyType aKey,
size_t aAmount,
void *aUserArg)
{
const EnumArgs *envp = reinterpret_cast<const EnumArgs*>(aUserArg);
nsAutoCString path("processes/");
path.Append(aKey);
nsAutoCString desc("This is the sum of all processes' '");
desc.Append(aKey);
desc.AppendLiteral("' numbers.");
envp->mHandleReport->Callback(NS_LITERAL_CSTRING("System"), path,
KIND_NONHEAP, UNITS_BYTES, aAmount,
desc, envp->mData);
return PL_DHASH_NEXT;
}
};
nsresult ReadMemInfo(int64_t* aMemTotal, int64_t* aMemFree)
{
FILE* f = fopen("/proc/meminfo", "r");
if (!f) {
return NS_ERROR_FAILURE;
}
int n1 = fscanf(f, "MemTotal: %" SCNd64 " kB\n", aMemTotal);
int n2 = fscanf(f, "MemFree: %" SCNd64 " kB\n", aMemFree);
fclose(f);
if (n1 != 1 || n2 != 1) {
return NS_ERROR_FAILURE;
}
// Convert from KB to B.
*aMemTotal *= 1024;
*aMemFree *= 1024;
return NS_OK;
}
nsresult CollectProcessReports(nsIHandleReportCallback* aHandleReport,
nsISupports* aData,
int64_t* aTotalPss)
{
*aTotalPss = 0;
ProcessSizes processSizes;
DIR* d = opendir("/proc");
if (NS_WARN_IF(!d)) {
return NS_ERROR_FAILURE;
}
struct dirent* ent;
while ((ent = readdir(d))) {
struct stat statbuf;
const char* pidStr = ent->d_name;
// Don't check the return value of stat() -- it can return -1 for these
// directories even when it has succeeded, apparently.
stat(pidStr, &statbuf);
if (S_ISDIR(statbuf.st_mode) && IsNumeric(pidStr)) {
nsCString processName("process(");
// Get the command name from cmdline. If that fails, the pid is still
// shown.
nsPrintfCString cmdlinePath("/proc/%s/cmdline", pidStr);
FILE* f = fopen(cmdlinePath.get(), "r");
if (f) {
static const size_t len = 256;
char buf[len];
if (fgets(buf, len, f)) {
processName.Append(buf);
// A hack: replace forward slashes with '\\' so they aren't treated
// as path separators. Consumers of this reporter (such as
// about:memory) have to undo this change.
processName.ReplaceChar('/', '\\');
processName.AppendLiteral(", ");
}
fclose(f);
}
processName.AppendLiteral("pid=");
processName.Append(pidStr);
processName.Append(')');
// Read the PSS values from the smaps file.
nsPrintfCString smapsPath("/proc/%s/smaps", pidStr);
f = fopen(smapsPath.get(), "r");
if (!f) {
// Processes can terminate between the readdir() call above and now,
// so just skip if we can't open the file.
continue;
}
nsresult rv = ParseMappings(f, processName, aHandleReport, aData,
&processSizes, aTotalPss);
fclose(f);
if (NS_FAILED(rv)) {
continue;
}
// Report the open file descriptors for this process.
nsPrintfCString procFdPath("/proc/%s/fd", pidStr);
rv = CollectOpenFileReports(
aHandleReport, aData, procFdPath, processName);
if (NS_FAILED(rv)) {
break;
}
}
}
closedir(d);
// Report the "processes/" tree.
processSizes.Report(aHandleReport, aData);
return NS_OK;
}
nsresult ParseMappings(FILE* aFile,
const nsACString& aProcessName,
nsIHandleReportCallback* aHandleReport,
nsISupports* aData,
ProcessSizes* aProcessSizes,
int64_t* aTotalPss)
{
// The first line of an entry in /proc/<pid>/smaps looks just like an entry
// in /proc/<pid>/maps:
//
// address perms offset dev inode pathname
// 02366000-025d8000 rw-p 00000000 00:00 0 [heap]
//
// Each of the following lines contains a key and a value, separated
// by ": ", where the key does not contain either of those characters.
// Assuming more than this about the structure of those lines has
// failed to be future-proof in the past, so we avoid doing so.
//
// This makes it difficult to detect the start of a new entry
// until it's been removed from the stdio buffer, so we just loop
// over all lines in the file in this routine.
const int argCount = 8;
unsigned long long addrStart, addrEnd;
char perms[5];
unsigned long long offset;
// The 2.6 and 3.0 kernels allocate 12 bits for the major device number and
// 20 bits for the minor device number. Future kernels might allocate more.
// 64 bits ought to be enough for anybody.
char devMajor[17];
char devMinor[17];
unsigned int inode;
char line[1025];
// This variable holds the path of the current entry, or is void
// if we're scanning for the start of a new entry.
nsAutoCString path;
int pathOffset;
path.SetIsVoid(true);
while (fgets(line, sizeof(line), aFile)) {
if (path.IsVoid()) {
int n = sscanf(line,
"%llx-%llx %4s %llx "
"%16[0-9a-fA-F]:%16[0-9a-fA-F] %u %n",
&addrStart, &addrEnd, perms, &offset, devMajor,
devMinor, &inode, &pathOffset);
if (n >= argCount - 1) {
path.Assign(line + pathOffset);
path.StripChars("\n");
}
continue;
}
// Now that we have a name and other metadata, scan for the PSS.
size_t pss_kb;
int n = sscanf(line, "Pss: %zu", &pss_kb);
if (n < 1) {
continue;
}
size_t pss = pss_kb * 1024;
if (pss > 0) {
nsAutoCString name, description, tag;
GetReporterNameAndDescription(path.get(), perms, name, description, tag);
nsAutoCString path("mem/processes/");
path.Append(aProcessName);
path.Append('/');
path.Append(name);
REPORT(path, pss, description);
// Increment the appropriate aProcessSizes values, and the total.
aProcessSizes->Add(tag, pss);
*aTotalPss += pss;
}
// Now that we've seen the PSS, we're done wit hthis entry.
path.SetIsVoid(true);
}
return NS_OK;
}
void GetReporterNameAndDescription(const char* aPath,
const char* aPerms,
nsACString& aName,
nsACString& aDesc,
nsACString& aTag)
{
aName.Truncate();
aDesc.Truncate();
aTag.Truncate();
// If aPath points to a file, we have its absolute path; it might
// also be a bracketed pseudo-name (see below). In either case
// there is also some whitespace to trim.
nsAutoCString absPath;
absPath.Append(aPath);
absPath.StripChars(" ");
if (absPath.EqualsLiteral("[heap]")) {
aName.AppendLiteral("anonymous/brk-heap");
aDesc.AppendLiteral(
"Memory in anonymous mappings within the boundaries defined by "
"brk() / sbrk(). This is likely to be just a portion of the "
"application's heap; the remainder lives in other anonymous mappings. "
"This corresponds to '[heap]' in /proc/<pid>/smaps.");
aTag = aName;
} else if (absPath.EqualsLiteral("[stack]")) {
aName.AppendLiteral("main-thread-stack");
aDesc.AppendLiteral(
"The stack size of the process's main thread. This corresponds to "
"'[stack]' in /proc/<pid>/smaps.");
aTag = aName;
} else if (absPath.EqualsLiteral("[vdso]")) {
aName.AppendLiteral("vdso");
aDesc.AppendLiteral(
"The virtual dynamically-linked shared object, also known as the "
"'vsyscall page'. This is a memory region mapped by the operating "
"system for the purpose of allowing processes to perform some "
"privileged actions without the overhead of a syscall.");
aTag = aName;
} else if (StringBeginsWith(absPath, NS_LITERAL_CSTRING("[anon:")) &&
EndsWithLiteral(absPath, "]")) {
// It's tagged memory; see also "mfbt/TaggedAnonymousMemory.h".
nsAutoCString tag(Substring(absPath, 6, absPath.Length() - 7));
aName.AppendLiteral("anonymous/");
aName.Append(tag);
aTag = aName;
aDesc.AppendLiteral("Memory in anonymous mappings tagged with '");
aDesc.Append(tag);
aDesc.Append('\'');
} else if (!IsAnonymous(absPath)) {
// We now know it's an actual file. Truncate this to its
// basename, and put the absolute path in the description.
nsAutoCString basename, dirname;
GetBasename(absPath, basename);
GetDirname(absPath, dirname);
// Hack: A file is a shared library if the basename contains ".so" and
// its dirname contains "/lib", or if the basename ends with ".so".
if (EndsWithLiteral(basename, ".so") ||
(basename.Find(".so") != -1 && dirname.Find("/lib") != -1)) {
aName.AppendLiteral("shared-libraries/");
aTag = aName;
if (strncmp(aPerms, "r-x", 3) == 0) {
aTag.AppendLiteral("read-executable");
} else if (strncmp(aPerms, "rw-", 3) == 0) {
aTag.AppendLiteral("read-write");
} else if (strncmp(aPerms, "r--", 3) == 0) {
aTag.AppendLiteral("read-only");
} else {
aTag.AppendLiteral("other");
}
} else {
aName.AppendLiteral("other-files");
if (EndsWithLiteral(basename, ".xpi")) {
aName.AppendLiteral("/extensions");
} else if (dirname.Find("/fontconfig") != -1) {
aName.AppendLiteral("/fontconfig");
}
aTag = aName;
aName.Append('/');
}
aName.Append(basename);
aDesc.Append(absPath);
} else {
if (MozTaggedMemoryIsSupported()) {
aName.AppendLiteral("anonymous/untagged");
aDesc.AppendLiteral("Memory in untagged anonymous mappings.");
aTag = aName;
} else {
aName.AppendLiteral("anonymous/outside-brk");
aDesc.AppendLiteral("Memory in anonymous mappings outside the "
"boundaries defined by brk() / sbrk().");
aTag = aName;
}
}
aName.AppendLiteral("/[");
aName.Append(aPerms);
aName.Append(']');
// Append the permissions. This is useful for non-verbose mode in
// about:memory when the filename is long and goes of the right side of the
// window.
aDesc.AppendLiteral(" [");
aDesc.Append(aPerms);
aDesc.Append(']');
}
nsresult CollectPmemReports(nsIHandleReportCallback* aHandleReport,
nsISupports* aData)
{
// The pmem subsystem allocates physically contiguous memory for
// interfacing with hardware. In order to ensure availability,
// this memory is reserved during boot, and allocations are made
// within these regions at runtime.
//
// There are typically several of these pools allocated at boot.
// The /sys/kernel/pmem_regions directory contains a subdirectory
// for each one. Within each subdirectory, the files we care
// about are "size" (the total amount of physical memory) and
// "mapped_regions" (a list of the current allocations within that
// area).
DIR* d = opendir("/sys/kernel/pmem_regions");
if (!d) {
if (NS_WARN_IF(errno != ENOENT)) {
return NS_ERROR_FAILURE;
}
// If ENOENT, system doesn't use pmem.
return NS_OK;
}
struct dirent* ent;
while ((ent = readdir(d))) {
const char* name = ent->d_name;
uint64_t size;
int scanned;
// Skip "." and ".." (and any other dotfiles).
if (name[0] == '.') {
continue;
}
// Read the total size. The file gives the size in decimal and
// hex, in the form "13631488(0xd00000)"; we parse the former.
nsPrintfCString sizePath("/sys/kernel/pmem_regions/%s/size", name);
FILE* sizeFile = fopen(sizePath.get(), "r");
if (NS_WARN_IF(!sizeFile)) {
continue;
}
scanned = fscanf(sizeFile, "%" SCNu64, &size);
if (NS_WARN_IF(scanned != 1)) {
continue;
}
fclose(sizeFile);
// Read mapped regions; format described below.
uint64_t freeSize = size;
nsPrintfCString regionsPath("/sys/kernel/pmem_regions/%s/mapped_regions",
name);
FILE* regionsFile = fopen(regionsPath.get(), "r");
if (regionsFile) {
static const size_t bufLen = 4096;
char buf[bufLen];
while (fgets(buf, bufLen, regionsFile)) {
int pid;
// Skip header line.
if (strncmp(buf, "pid #", 5) == 0) {
continue;
}
// Line format: "pid N:" + zero or more "(Start,Len) ".
// N is decimal; Start and Len are in hex.
scanned = sscanf(buf, "pid %d", &pid);
if (NS_WARN_IF(scanned != 1)) {
continue;
}
for (const char* nextParen = strchr(buf, '(');
nextParen != nullptr;
nextParen = strchr(nextParen + 1, '(')) {
uint64_t mapStart, mapLen;
scanned = sscanf(nextParen + 1, "%" SCNx64 ",%" SCNx64,
&mapStart, &mapLen);
if (NS_WARN_IF(scanned != 2)) {
break;
}
nsPrintfCString path("mem/pmem/used/%s/segment(pid=%d, "
"offset=0x%" PRIx64 ")", name, pid, mapStart);
nsPrintfCString desc("Physical memory reserved for the \"%s\" pool "
"and allocated to a buffer.", name);
REPORT_WITH_CLEANUP(path, UNITS_BYTES, mapLen, desc,
(fclose(regionsFile), closedir(d)));
freeSize -= mapLen;
}
}
fclose(regionsFile);
}
nsPrintfCString path("mem/pmem/free/%s", name);
nsPrintfCString desc("Physical memory reserved for the \"%s\" pool and "
"unavailable to the rest of the system, but not "
"currently allocated.", name);
REPORT_WITH_CLEANUP(path, UNITS_BYTES, freeSize, desc, closedir(d));
}
closedir(d);
return NS_OK;
}
uint64_t
ReadSizeFromFile(const char* aFilename)
{
FILE* sizeFile = fopen(aFilename, "r");
if (NS_WARN_IF(!sizeFile)) {
return 0;
}
uint64_t size = 0;
fscanf(sizeFile, "%" SCNu64, &size);
fclose(sizeFile);
return size;
}
nsresult
CollectZramReports(nsIHandleReportCallback* aHandleReport,
nsISupports* aData)
{
// zram usage stats files can be found under:
// /sys/block/zram<id>
// |--> disksize - Maximum amount of uncompressed data that can be
// stored on the disk (bytes)
// |--> orig_data_size - Uncompressed size of data in the disk (bytes)
// |--> compr_data_size - Compressed size of the data in the disk (bytes)
// |--> num_reads - Number of attempted reads to the disk (count)
// |--> num_writes - Number of attempted writes to the disk (count)
//
// Each file contains a single integer value in decimal form.
DIR* d = opendir("/sys/block");
if (!d) {
if (NS_WARN_IF(errno != ENOENT)) {
return NS_ERROR_FAILURE;
}
return NS_OK;
}
struct dirent* ent;
while ((ent = readdir(d))) {
const char* name = ent->d_name;
// Skip non-zram entries.
if (strncmp("zram", name, 4) != 0) {
continue;
}
// Report disk size statistics.
nsPrintfCString diskSizeFile("/sys/block/%s/disksize", name);
nsPrintfCString origSizeFile("/sys/block/%s/orig_data_size", name);
uint64_t diskSize = ReadSizeFromFile(diskSizeFile.get());
uint64_t origSize = ReadSizeFromFile(origSizeFile.get());
uint64_t unusedSize = diskSize - origSize;
nsPrintfCString diskUsedPath("zram-disksize/%s/used", name);
nsPrintfCString diskUsedDesc(
"The uncompressed size of data stored in \"%s.\" "
"This excludes zero-filled pages since "
"no memory is allocated for them.", name);
REPORT_WITH_CLEANUP(diskUsedPath, UNITS_BYTES, origSize,
diskUsedDesc, closedir(d));
nsPrintfCString diskUnusedPath("zram-disksize/%s/unused", name);
nsPrintfCString diskUnusedDesc(
"The amount of uncompressed data that can still be "
"be stored in \"%s\"", name);
REPORT_WITH_CLEANUP(diskUnusedPath, UNITS_BYTES, unusedSize,
diskUnusedDesc, closedir(d));
// Report disk accesses.
nsPrintfCString readsFile("/sys/block/%s/num_reads", name);
nsPrintfCString writesFile("/sys/block/%s/num_writes", name);
uint64_t reads = ReadSizeFromFile(readsFile.get());
uint64_t writes = ReadSizeFromFile(writesFile.get());
nsPrintfCString readsDesc(
"The number of reads (failed or successful) done on "
"\"%s\"", name);
nsPrintfCString readsPath("zram-accesses/%s/reads", name);
REPORT_WITH_CLEANUP(readsPath, UNITS_COUNT_CUMULATIVE, reads,
readsDesc, closedir(d));
nsPrintfCString writesDesc(
"The number of writes (failed or successful) done "
"on \"%s\"", name);
nsPrintfCString writesPath("zram-accesses/%s/writes", name);
REPORT_WITH_CLEANUP(writesPath, UNITS_COUNT_CUMULATIVE, writes,
writesDesc, closedir(d));
// Report compressed data size.
nsPrintfCString comprSizeFile("/sys/block/%s/compr_data_size", name);
uint64_t comprSize = ReadSizeFromFile(comprSizeFile.get());
nsPrintfCString comprSizeDesc(
"The compressed size of data stored in \"%s\"",
name);
nsPrintfCString comprSizePath("zram-compr-data-size/%s", name);
REPORT_WITH_CLEANUP(comprSizePath, UNITS_BYTES, comprSize,
comprSizeDesc, closedir(d));
}
closedir(d);
return NS_OK;
}
nsresult
CollectOpenFileReports(nsIHandleReportCallback* aHandleReport,
nsISupports* aData,
const nsACString& aProcPath,
const nsACString& aProcessName)
{
// All file descriptors opened by a process are listed under
// /proc/<pid>/fd/<numerical_fd>. Each entry is a symlink that points to the
// path that was opened. This can be an actual file, a socket, a pipe, an
// anon_inode, or possibly an uncategorized device.
const char kFilePrefix[] = "/";
const char kSocketPrefix[] = "socket:";
const char kPipePrefix[] = "pipe:";
const char kAnonInodePrefix[] = "anon_inode:";
const nsCString procPath(aProcPath);
DIR* d = opendir(procPath.get());
if (!d) {
if (NS_WARN_IF(errno != ENOENT && errno != EACCES)) {
return NS_ERROR_FAILURE;
}
return NS_OK;
}
char linkPath[PATH_MAX + 1];
struct dirent* ent;
while ((ent = readdir(d))) {
const char* fd = ent->d_name;
// Skip "." and ".." (and any other dotfiles).
if (fd[0] == '.') {
continue;
}
nsPrintfCString fullPath("%s/%s", procPath.get(), fd);
ssize_t linkPathSize = readlink(fullPath.get(), linkPath, PATH_MAX);
if (linkPathSize > 0) {
linkPath[linkPathSize] = '\0';
#define CHECK_PREFIX(prefix) \
(strncmp(linkPath, prefix, sizeof(prefix) - 1) == 0)
const char* category = nullptr;
const char* descriptionPrefix = nullptr;
if (CHECK_PREFIX(kFilePrefix)) {
category = "files"; // No trailing slash, the file path will have one
descriptionPrefix = "An open";
} else if (CHECK_PREFIX(kSocketPrefix)) {
category = "sockets/";
descriptionPrefix = "A socket";
} else if (CHECK_PREFIX(kPipePrefix)) {
category = "pipes/";
descriptionPrefix = "A pipe";
} else if (CHECK_PREFIX(kAnonInodePrefix)) {
category = "anon_inodes/";
descriptionPrefix = "An anon_inode";
} else {
category = "";
descriptionPrefix = "An uncategorized";
}
#undef CHECK_PREFIX
const nsCString processName(aProcessName);
nsPrintfCString entryPath(
"open-fds/%s/%s%s/%s", processName.get(), category, linkPath, fd);
nsPrintfCString entryDescription(
"%s file descriptor opened by the process", descriptionPrefix);
REPORT_WITH_CLEANUP(
entryPath, UNITS_COUNT, 1, entryDescription, closedir(d));
}
}
closedir(d);
return NS_OK;
}
#undef REPORT
};
NS_IMPL_ISUPPORTS(SystemReporter, nsIMemoryReporter)
void
Init()
{
RegisterStrongMemoryReporter(new SystemReporter());
}
} // namespace SystemMemoryReporter
} // namespace mozilla