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Commit 1e563585 authored by George Nachman's avatar George Nachman
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Add Poll helper and debugging code to track down bug where poll() doesn't return on EOF sometimes.

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PTYTask.m
+ 19
− 3
View file @ 1e563585
@@ -4,7 +4,7 @@
// Use this instead to debug this module:
// #define PtyTaskDebugLog NSLog
 
#define MAXRW 1024
#define MAXRW 1
 
#import "PTYTask.h"
#import "Coprocess.h"
@@ -23,6 +23,8 @@
#include <sys/user.h>
#include <unistd.h>
#include <util.h>
#import "DebugLogging.h"
#import "iTermPollHelper.h"
 
#define CTRLKEY(c) ((c)-'A'+1)
 
@@ -175,8 +177,13 @@ static void reapchild(int n)
path = [progpath copy];
 
setup_tty_param(&term, &win, width, height, isUTF8);
// Register a handler for the child death signal.
signal(SIGCHLD, reapchild);
// Block SIGCHLD
sigset_t signal_set;
sigemptyset(&signal_set);
sigaddset(&signal_set, SIGCHLD);
sigprocmask(SIG_BLOCK, &signal_set, NULL);
const char* argpath;
argpath = [[progpath stringByStandardizingPath] UTF8String];
 
@@ -281,6 +288,12 @@ static void reapchild(int n)
for (int i = 0; i < iterations; ++i) {
// Only read up to MAXRW*iterations bytes, then release control
ssize_t n = read(fd, buffer + bytesRead, MAXRW);
LOG(@"read returns %d", (int)n);
int theError = errno;
if (n == 0) {
[self brokenPipe];
return;
}
if (n < 0) {
// There was a read error.
if (errno != EAGAIN && errno != EINTR) {
@@ -305,6 +318,7 @@ static void reapchild(int n)
 
hasOutput = YES;
 
// NSLog(@"%.*s", bytesRead, buffer);
// Send data to the terminal
[self readTask:buffer length:bytesRead];
}
@@ -381,6 +395,7 @@ static void reapchild(int n)
 
- (void)brokenPipe
{
NSLog(@"* BROKEN PIPE *");
brokenPipe_ = YES;
[[TaskNotifier sharedInstance] deregisterTask:self];
[(NSObject *)self.delegate performSelectorOnMainThread:@selector(brokenPipe)
@@ -447,6 +462,7 @@ static void reapchild(int n)
// being passed a half-broken fd. We must change it because after this
// function returns, a new task may be created with this fd and then
// the select thread wouldn't know which task a fd belongs to.
DLog(@"Stop called from %@", [NSThread callStackSymbols]);
fd = -1;
}
}
TaskNotifier.m
+ 35
− 79
View file @ 1e563585
@@ -10,8 +10,9 @@
#import "Coprocess.h"
#import "DebugLogging.h"
#import "PTYTask.h"
#import "iTermPollHelper.h"
 
#define PtyTaskDebugLog(args...)
#define PtyTaskDebugLog DLog
 
NSString *const kTaskNotifierDidSpin = @"kTaskNotifierDidSpin";
 
@@ -129,17 +130,13 @@ NSString *const kTaskNotifierDidSpin = @"kTaskNotifierDidSpin";
NSEnumerator* iter;
PTYTask* task;
NSAutoreleasePool* autoreleasePool = [[NSAutoreleasePool alloc] init];
iTermPollHelper *pollHelper = [[iTermPollHelper alloc] init];
// FIXME: replace this with something better...
for(;;) {
FD_ZERO(&rfds);
FD_ZERO(&wfds);
FD_ZERO(&efds);
while (1) {
[pollHelper reset];
// Unblock pipe to interrupt select() whenever a PTYTask register/unregisters
highfd = unblockPipeR;
FD_SET(unblockPipeR, &rfds);
[pollHelper addFileDescriptor:unblockPipeR forReading:YES writing:NO identifier:nil];
NSMutableSet* handledFds = [[NSMutableSet alloc] initWithCapacity:[tasks count]];
// Add all the PTYTask pipes
@@ -184,48 +181,26 @@ NSString *const kTaskNotifierDidSpin = @"kTaskNotifierDidSpin";
while ((task = [iter nextObject])) {
PtyTaskDebugLog(@"Got task %d\n", i);
int fd = [task fd];
if (fd < 0) {
PtyTaskDebugLog(@"Task has fd of %d\n", fd);
} else {
// PtyTaskDebugLog(@"Select on fd %d\n", fd);
if (fd > highfd)
highfd = fd;
if ([task wantsRead])
FD_SET(fd, &rfds);
if ([task wantsWrite])
FD_SET(fd, &wfds);
FD_SET(fd, &efds);
PtyTaskDebugLog(@"Task has fd of %d\n", fd);
if (fd >= 0) {
[pollHelper addFileDescriptor:fd
forReading:[task wantsRead]
writing:[task wantsWrite]
identifier:task];
}
@synchronized (task) {
Coprocess *coprocess = [task coprocess];
if (coprocess) {
if ([coprocess wantToRead] && [task writeBufferHasRoom]) {
int rfd = [coprocess readFileDescriptor];
if (rfd > highfd) {
highfd = rfd;
}
FD_SET(rfd, &rfds);
}
if ([coprocess wantToWrite]) {
int wfd = [coprocess writeFileDescriptor];
if (wfd > highfd) {
highfd = wfd;
}
FD_SET(wfd, &wfds);
}
if (![coprocess eof]) {
int rfd = [coprocess readFileDescriptor];
if (rfd > highfd) {
highfd = rfd;
}
FD_SET(rfd, &efds);
int wfd = [coprocess writeFileDescriptor];
if (wfd > highfd) {
highfd = wfd;
}
FD_SET(wfd, &efds);
}
BOOL reading = ([coprocess wantToRead] && [task writeBufferHasRoom]) || ![coprocess eof];
[pollHelper addFileDescriptor:[coprocess readFileDescriptor]
forReading:reading
writing:NO
identifier:coprocess];
[pollHelper addFileDescriptor:[coprocess writeFileDescriptor]
forReading:NO
writing:[coprocess wantToWrite]
identifier:coprocess];
}
}
++i;
@@ -237,18 +212,13 @@ NSString *const kTaskNotifierDidSpin = @"kTaskNotifierDidSpin";
[[NSNotificationCenter defaultCenter] postNotificationName:kTaskNotifierDidSpin object:nil];
 
// Poll...
if (select(highfd+1, &rfds, &wfds, &efds, NULL) <= 0) {
switch(errno) {
case EAGAIN:
case EINTR:
default:
goto breakloop;
// If the file descriptor is closed in the main thread there's a race where sometimes you'll get an EBADF.
}
}
DLog(@"call poll...");
[pollHelper poll];
DLog(@"continuing after poll");
// Interrupted?
if (FD_ISSET(unblockPipeR, &rfds)) {
if ([pollHelper flagsForFd:unblockPipeR] & kiTermPollHelperFlagReadable) {
DLog(@"Interrupted");
char dummy[32];
do {
read(unblockPipeR, dummy, sizeof(dummy));
@@ -264,8 +234,8 @@ NSString *const kTaskNotifierDidSpin = @"kTaskNotifierDidSpin";
BOOL notifyOfCoprocessChange = NO;
while ((task = [iter nextObject])) {
PtyTaskDebugLog(@"Got task %d\n", i);
int fd = [task fd];
PtyTaskDebugLog(@"Got task %d, fd=%d\n", i, fd);
if (fd >= 0) {
// This is mostly paranoia, but if two threads
// end up with the same fd (because one closed
@@ -279,7 +249,8 @@ NSString *const kTaskNotifierDidSpin = @"kTaskNotifierDidSpin";
[task retain];
[handledFds addObject:[NSNumber numberWithInt:fd]];
if (FD_ISSET(fd, &rfds)) {
NSUInteger taskFlags = [pollHelper flagsForFd:fd];
if (taskFlags & kiTermPollHelperFlagReadable) {
PtyTaskDebugLog(@"run/processRead: unlock");
[tasksLock unlock];
[task processRead];
@@ -291,7 +262,7 @@ NSString *const kTaskNotifierDidSpin = @"kTaskNotifierDidSpin";
iter = [tasks objectEnumerator];
}
}
if (FD_ISSET(fd, &wfds)) {
if (taskFlags & kiTermPollHelperFlagWritable) {
PtyTaskDebugLog(@"run/processWrite: unlock");
[tasksLock unlock];
[task processWrite];
@@ -303,20 +274,6 @@ NSString *const kTaskNotifierDidSpin = @"kTaskNotifierDidSpin";
iter = [tasks objectEnumerator];
}
}
if (FD_ISSET(fd, &efds)) {
PtyTaskDebugLog(@"run/brokenPipe: unlock");
[tasksLock unlock];
// brokenPipe will call deregisterTask and add the pid to
// deadpool.
[task brokenPipe];
PtyTaskDebugLog(@"run/brokenPipe: lock");
[tasksLock lock];
if (tasksChanged) {
PtyTaskDebugLog(@"Restart iteration\n");
tasksChanged = NO;
iter = [tasks objectEnumerator];
}
}
// Move input around between coprocess and main process.
if ([task fd] >= 0 && ![task hasBrokenPipe]) { // Make sure the pipe wasn't just broken.
@@ -329,7 +286,8 @@ NSString *const kTaskNotifierDidSpin = @"kTaskNotifierDidSpin";
continue;
}
[handledFds addObject:[NSNumber numberWithInt:fd]];
if (![coprocess eof] && FD_ISSET(fd, &rfds)) {
NSUInteger coprocessFlags = [pollHelper flagsForFd:fd];
if (![coprocess eof] && (coprocessFlags & kiTermPollHelperFlagReadable)) {
[coprocess read];
[task writeTask:coprocess.inputBuffer];
[coprocess.inputBuffer setLength:0];
@@ -339,15 +297,13 @@ NSString *const kTaskNotifierDidSpin = @"kTaskNotifierDidSpin";
}
fd = [coprocess writeFileDescriptor];
coprocessFlags = [pollHelper flagsForFd:fd];
if ([handledFds containsObject:[NSNumber numberWithInt:fd]]) {
NSLog(@"Duplicate fd %d", fd);
continue;
}
[handledFds addObject:[NSNumber numberWithInt:fd]];
if (FD_ISSET(fd, &efds)) {
coprocess.eof = YES;
}
if (FD_ISSET(fd, &wfds)) {
if (coprocessFlags & kiTermPollHelperFlagWritable) {
if (![coprocess eof]) {
[coprocess write];
}
iTerm.xcodeproj/project.pbxproj
+ 10
− 0
View file @ 1e563585
@@ -747,6 +747,9 @@
A6A5991D1887C63700CB4209 /* ToolCommandHistoryView.h in Headers */ = {isa = PBXBuildFile; fileRef = A6A5991B1887C63700CB4209 /* ToolCommandHistoryView.h */; };
A6A5991E1887C63700CB4209 /* ToolCommandHistoryView.m in Sources */ = {isa = PBXBuildFile; fileRef = A6A5991C1887C63700CB4209 /* ToolCommandHistoryView.m */; };
A6A5991F1887C63700CB4209 /* ToolCommandHistoryView.m in Sources */ = {isa = PBXBuildFile; fileRef = A6A5991C1887C63700CB4209 /* ToolCommandHistoryView.m */; };
A6B5133018E3CD2900D249A5 /* iTermPollHelper.h in Headers */ = {isa = PBXBuildFile; fileRef = A6B5132E18E3CD2900D249A5 /* iTermPollHelper.h */; };
A6B5133118E3CD2900D249A5 /* iTermPollHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = A6B5132F18E3CD2900D249A5 /* iTermPollHelper.m */; };
A6B5133218E3CD2900D249A5 /* iTermPollHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = A6B5132F18E3CD2900D249A5 /* iTermPollHelper.m */; };
A6C4E8E01846E13800CFAA77 /* IntervalTree.m in Sources */ = {isa = PBXBuildFile; fileRef = A6C4E8DC1846E13800CFAA77 /* IntervalTree.m */; };
A6C4E8E11846E13800CFAA77 /* IntervalTree.m in Sources */ = {isa = PBXBuildFile; fileRef = A6C4E8DC1846E13800CFAA77 /* IntervalTree.m */; };
A6C4E8E21846E13800CFAA77 /* IntervalTree.h in Headers */ = {isa = PBXBuildFile; fileRef = A6C4E8DD1846E13800CFAA77 /* IntervalTree.h */; };
@@ -1291,6 +1294,8 @@
A6A13ABA18C34F6400B241ED /* VT100XtermParser.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = VT100XtermParser.m; sourceTree = "<group>"; };
A6A5991B1887C63700CB4209 /* ToolCommandHistoryView.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ToolCommandHistoryView.h; sourceTree = "<group>"; };
A6A5991C1887C63700CB4209 /* ToolCommandHistoryView.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ToolCommandHistoryView.m; sourceTree = "<group>"; };
A6B5132E18E3CD2900D249A5 /* iTermPollHelper.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = iTermPollHelper.h; sourceTree = "<group>"; };
A6B5132F18E3CD2900D249A5 /* iTermPollHelper.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = iTermPollHelper.m; sourceTree = "<group>"; };
A6C4E8DC1846E13800CFAA77 /* IntervalTree.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = IntervalTree.m; sourceTree = "<group>"; };
A6C4E8DD1846E13800CFAA77 /* IntervalTree.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = IntervalTree.h; sourceTree = "<group>"; };
A6C4E8E61846E32600CFAA77 /* IntervalTreeTest.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = IntervalTreeTest.m; path = iTermTests/IntervalTreeTest.m; sourceTree = "<group>"; };
@@ -1449,6 +1454,8 @@
0464AB0D006CD2EC7F000001 /* JTerminal */ = {
isa = PBXGroup;
children = (
A6B5132E18E3CD2900D249A5 /* iTermPollHelper.h */,
A6B5132F18E3CD2900D249A5 /* iTermPollHelper.m */,
0464AB0E006CD2EC7F000001 /* Classes */,
0464AB15006CD2EC7F000001 /* Headers */,
0464AB1F006CD2EC7F000001 /* Other Sources */,
@@ -2448,6 +2455,7 @@
1D9F6AB8140C9DC4009B5CD4 /* FutureMethods.h in Headers */,
1DE8DC891415513A00F83147 /* ToolbeltView.h in Headers */,
1DE8DC8D1415546000F83147 /* ToolProfiles.h in Headers */,
A6B5133018E3CD2900D249A5 /* iTermPollHelper.h in Headers */,
1DE8DDAD1415648600F83147 /* ToolPasteHistory.h in Headers */,
1DE8DF361415799700F83147 /* ToolWrapper.h in Headers */,
1D19C71414171F1D00617E08 /* ToolJobs.h in Headers */,
@@ -2809,6 +2817,7 @@
A647E39C18C3515900450FA1 /* VT100AnsiParser.m in Sources */,
A68A3111186E2EDA007F550F /* PopupEntry.m in Sources */,
1D9A552D180FA69900B42CE9 /* SearchResult.m in Sources */,
A6B5133218E3CD2900D249A5 /* iTermPollHelper.m in Sources */,
A63F409C183B3AA7003A6A6D /* PTYNoteView.m in Sources */,
1D9A55AB180FA8B700B42CE9 /* PSMProgressIndicator.m in Sources */,
1D9A5593180FA87000B42CE9 /* PTYFontInfo.m in Sources */,
@@ -3127,6 +3136,7 @@
1D988598135D23BD0072023F /* ProcessCache.m in Sources */,
A68A30DC186D1429007F550F /* SCPFile.m in Sources */,
1D624BC81386E09E00111319 /* GTMCarbonEvent.m in Sources */,
A6B5133118E3CD2900D249A5 /* iTermPollHelper.m in Sources */,
1DA8117F13CEA30A00CCA89A /* FontSizeEstimator.m in Sources */,
1D81F0C1183C3C2D00910838 /* NSView+RecursiveDescription.m in Sources */,
1DCA5ED013EE507800B7725E /* WindowArrangements.m in Sources */,
iTermPollHelper.h 0 → 100644
+ 31
− 0
View file @ 1e563585
//
// iTermPollHelper.h
// iTerm
//
// Created by George Nachman on 3/26/14.
//
//
#import <Foundation/Foundation.h>
#define kiTermPollHelperFlagReadable (1 << 0)
#define kiTermPollHelperFlagWritable (1 << 1)
extern NSMutableString *gLog;
#define LOG(args...) \
do { \
[gLog appendFormat:args]; \
[gLog appendString:@"\n"]; \
} while (0);
@interface iTermPollHelper : NSObject
- (void)reset;
- (void)addFileDescriptor:(int)fd
forReading:(BOOL)reading
writing:(BOOL)writing
identifier:(NSObject *)identifier;
- (void)poll;
- (NSUInteger)flagsForFd:(int)fd;
@end
iTermPollHelper.m 0 → 100644
+ 146
− 0
View file @ 1e563585
//
// iTermPollHelper.m
// iTerm
//
// Created by George Nachman on 3/26/14.
//
//
#import "iTermPollHelper.h"
#include <poll.h>
char gBuffer[100];
@interface CStructMutableArray : NSObject
@property(nonatomic, readonly) int count;
- (id)initWithStructSize:(size_t)structSize;
- (void)addObjectWithBlock:(void (^)(void *ptr))assignBlock;
- (void *)pointerToObjectAtIndex:(NSInteger)index;
@end
@implementation CStructMutableArray {
char *_storage;
size_t _structSize;
int _count;
int _capacity;
}
- (id)initWithStructSize:(size_t)structSize {
self = [super init];
if (self) {
_capacity = 1;
_structSize = structSize;
_storage = calloc(_capacity, _structSize);
}
return self;
}
- (int)count {
return _count;
}
- (void)addObjectWithBlock:(void (^)(void *ptr))assignBlock {
if (_capacity == _count) {
int originalSizeInBytes = _capacity * _structSize;
_capacity *= 2;
_storage = realloc(_storage, _capacity * _structSize);
memset(_storage + originalSizeInBytes, 0, originalSizeInBytes);
}
int index = _count;
++_count;
assignBlock(_storage + (_structSize * index));
}
- (void *)pointerToObjectAtIndex:(NSInteger)index {
assert(index >= 0 && index < _count);
return _storage + (_structSize * index);
}
@end
@implementation iTermPollHelper {
CStructMutableArray *_fds;
NSMutableArray *_identifiers; // parallel to fds
NSMutableDictionary *_index; // file descriptor -> index
}
NSMutableString *gLog;
- (id)init {
gLog = [[NSMutableString alloc] init];
self = [super init];
if (self) {
_fds = [[CStructMutableArray alloc] initWithStructSize:sizeof(struct pollfd)];
_identifiers = [[NSMutableArray alloc] init];
_index = [[NSMutableDictionary alloc] init];
}
return self;
}
- (void)reset {
LOG(@"Reset");
[_fds release];
_fds = [[CStructMutableArray alloc] initWithStructSize:sizeof(struct pollfd)];
[_identifiers removeAllObjects];
[_index removeAllObjects];
}
- (void)addFileDescriptor:(int)fd
forReading:(BOOL)reading
writing:(BOOL)writing
identifier:(NSObject *)identifier {
LOG(@"Poll on %d", fd);
_index[@(fd)] = @(_fds.count);
[_identifiers addObject:identifier ?: [NSNull null]];
[_fds addObjectWithBlock:^(void *ptr) {
struct pollfd *pollfd = (struct pollfd *)ptr;
pollfd->fd = fd;
pollfd->events = ((reading ? (POLLIN) : 0) | (writing ? POLLOUT : 0));
pollfd->revents = 0;
}];
}
void TryReadingFromFd(int fd) {
char buffer[1];
int n = read(fd, buffer, 1);
NSLog(@"Read returns %d, errno=%d", n, errno);
}
- (void)poll {
struct pollfd *pollfds = [_fds pointerToObjectAtIndex:0];
int count = _fds.count;
int numDescriptors;
do {
LOG(@"Start poll");
numDescriptors = poll(pollfds, count, -1);
LOG(@"Return from poll");
assert(numDescriptors != 0);
if (numDescriptors < 0) {
assert(errno == EAGAIN || errno == EINTR);
}
} while (numDescriptors < 0);
}
- (NSUInteger)flagsForFd:(int)fd {
NSNumber *n = _index[@(fd)];
if (!n) {
return 0;
}
int index = [n intValue];
struct pollfd *pollfd = [_fds pointerToObjectAtIndex:index];
NSUInteger flags = 0;
assert(!(pollfd->revents & POLLNVAL));
if (pollfd->revents & (POLLIN | POLLERR | POLLHUP)) {
LOG(@"fd %d is readable", fd);
flags |= kiTermPollHelperFlagReadable;
}
if (pollfd->revents & POLLOUT) {
LOG(@"fd %d is writable", fd);
flags |= kiTermPollHelperFlagWritable;
}
return flags;
}
@end
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