Files
clang-p2996/lldb/source/Plugins/Process/Linux/ProcFileReader.cpp
Zachary Turner bf9a77305f Move classes from Core -> Utility.
This moves the following classes from Core -> Utility.

ConstString
Error
RegularExpression
Stream
StreamString

The goal here is to get lldbUtility into a state where it has
no dependendencies except on itself and LLVM, so it can be the
starting point at which to start untangling LLDB's dependencies.
These are all low level and very widely used classes, and
previously lldbUtility had dependencies up to lldbCore in order
to use these classes.  So moving then down to lldbUtility makes
sense from both the short term and long term perspective in
solving this problem.

Differential Revision: https://reviews.llvm.org/D29427

llvm-svn: 293941
2017-02-02 21:39:50 +00:00

104 lines
3.0 KiB
C++

//===-- ProcFileReader.cpp --------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "Plugins/Process/Linux/ProcFileReader.h"
// C Headers
#include <fcntl.h>
#include <inttypes.h>
#include <limits.h>
#include <stdio.h>
#include <sys/stat.h>
// C++ Headers
#include <fstream>
// LLDB Headers
#include "lldb/Core/DataBufferHeap.h"
#include "lldb/Utility/Error.h"
using namespace lldb_private;
using namespace lldb_private::process_linux;
lldb::DataBufferSP ProcFileReader::ReadIntoDataBuffer(lldb::pid_t pid,
const char *name) {
int fd;
char path[PATH_MAX];
// Make sure we've got a nil terminated buffer for all the folks calling
// GetBytes() directly off our returned DataBufferSP if we hit an error.
lldb::DataBufferSP buf_sp(new DataBufferHeap(1, 0));
// Ideally, we would simply create a FileSpec and call ReadFileContents.
// However, files in procfs have zero size (since they are, in general,
// dynamically generated by the kernel) which is incompatible with the
// current ReadFileContents implementation. Therefore we simply stream the
// data into a DataBuffer ourselves.
if (snprintf(path, PATH_MAX, "/proc/%" PRIu64 "/%s", pid, name) > 0) {
if ((fd = open(path, O_RDONLY, 0)) >= 0) {
size_t bytes_read = 0;
std::unique_ptr<DataBufferHeap> buf_ap(new DataBufferHeap(1024, 0));
for (;;) {
size_t avail = buf_ap->GetByteSize() - bytes_read;
ssize_t status = read(fd, buf_ap->GetBytes() + bytes_read, avail);
if (status < 0)
break;
if (status == 0) {
buf_ap->SetByteSize(bytes_read);
buf_sp.reset(buf_ap.release());
break;
}
bytes_read += status;
if (avail - status == 0)
buf_ap->SetByteSize(2 * buf_ap->GetByteSize());
}
close(fd);
}
}
return buf_sp;
}
Error ProcFileReader::ProcessLineByLine(
lldb::pid_t pid, const char *name,
std::function<bool(const std::string &line)> line_parser) {
Error error;
// Try to open the /proc/{pid}/maps entry.
char filename[PATH_MAX];
snprintf(filename, sizeof(filename), "/proc/%" PRIu64 "/%s", pid, name);
filename[sizeof(filename) - 1] = '\0';
std::ifstream proc_file(filename);
if (proc_file.fail()) {
error.SetErrorStringWithFormat("failed to open file '%s'", filename);
return error;
}
// Read the file line by line, processing until either end of file or when the
// line_parser returns false.
std::string line;
bool should_continue = true;
while (should_continue && std::getline(proc_file, line)) {
// Pass the line over to the line_parser for processing. If the line_parser
// returns false, we
// stop processing.
should_continue = line_parser(line);
}
return error;
}