//
// "$Id: ExternalCodeEditor_UNIX.cxx 11878 2016-08-16 20:42:22Z greg.ercolano $".
//
// External code editor management class for Unix
//
#ifndef WIN32 /* This entire file unix only */
#include <errno.h> /* errno */
#include <string.h> /* strerror() */
#include <sys/types.h> /* stat().. */
#include <sys/stat.h>
#include <sys/wait.h> /* waitpid().. */
#include <fcntl.h> /* open().. */
#include <signal.h> /* kill().. */
#include <unistd.h>
#include <stdlib.h> /* free().. */
#include <stdio.h> /* snprintf().. */
#include <FL/Fl.H> /* Fl_Timeout_Handler.. */
#include <FL/fl_ask.H> /* fl_alert() */
#include "ExternalCodeEditor_UNIX.h"
extern int G_debug; // defined in fluid.cxx
// Static local data
static int L_editors_open = 0; // keep track of #editors open
static Fl_Timeout_Handler L_update_timer_cb = 0; // app's update timer callback
// [Static/Local] See if file exists
static int is_file(const char *filename) {
struct stat buf;
if ( stat(filename, &buf) < 0 ) return(0);
return(S_ISREG(buf.st_mode) ? 1 : 0); // regular file?
}
// [Static/Local] See if dir exists
static int is_dir(const char *dirname) {
struct stat buf;
if ( stat(dirname, &buf) < 0 ) return(0);
return(S_ISDIR(buf.st_mode) ? 1 : 0); // a dir?
}
// CTOR
ExternalCodeEditor::ExternalCodeEditor() {
pid_ = -1;
filename_ = 0;
file_mtime_ = 0;
file_size_ = 0;
}
// DTOR
ExternalCodeEditor::~ExternalCodeEditor() {
if ( G_debug )
printf("ExternalCodeEditor() DTOR CALLED (this=%p, pid=%ld)\n",
(void*)this, (long)pid_);
close_editor(); // close editor, delete tmp file
set_filename(0); // free()s filename
}
// [Protected] Set the filename. Handles memory allocation/free
// If set to NULL, frees memory.
//
void ExternalCodeEditor::set_filename(const char *val) {
if ( filename_ ) free((void*)filename_);
filename_ = val ? strdup(val) : 0;
}
// [Public] Is editor running?
int ExternalCodeEditor::is_editing() {
return( (pid_ != -1) ? 1 : 0 );
}
// [Protected] Wait for editor to close
void ExternalCodeEditor::close_editor() {
if ( G_debug ) printf("close_editor() called: pid=%ld\n", long(pid_));
// Wait until editor is closed + reaped
while ( is_editing() ) {
switch ( reap_editor() ) {
case -1: // error
fl_alert("Error reaping external editor\n"
"pid=%ld file=%s", long(pid_), filename());
break;
case 0: // process still running
switch ( fl_choice("Please close external editor\npid=%ld file=%s",
"Force Close", // button 0
"Closed", // button 1
0, // button 2
long(pid_), filename() ) ) {
case 0: // Force Close
kill_editor();
continue;
case 1: // Closed? try to reap
continue;
}
break;
default: // process reaped
return;
}
}
}
// [Protected] Kill the running editor (if any)
// Kills the editor, reaps the process, and removes the tmp file.
// The dtor calls this to ensure no editors remain running when fluid exits.
//
void ExternalCodeEditor::kill_editor() {
if ( G_debug ) printf("kill_editor() called: pid=%ld\n", (long)pid_);
if ( !is_editing() ) return; // editor not running? return..
kill(pid_, SIGTERM); // kill editor
int wcount = 0;
while ( pid_ != -1 ) { // and wait for it to finish..
usleep(100000); // 1/10th sec delay gives editor time to close itself
switch (reap_editor()) {
case -1: // error
fl_alert("Can't seem to close editor of file: %s\n"
"waitpid() returned: %s\n"
"Please close editor and hit OK",
filename(), strerror(errno));
continue;
case 0: // process still running
if ( ++wcount > 3 ) { // retry 3x with 1/10th delay before showing dialog
fl_alert("Can't seem to close editor of file: %s\n"
"Please close editor and hit OK", filename());
}
continue;
default: // process reaped
if ( G_debug )
printf("*** REAPED KILLED EXTERNAL EDITOR: PID %ld\n", (long)pid_);
pid_ = -1;
break;
}
}
return;
}
// [Public] Handle if file changed since last check, and update records if so.
// Load new data into 'code', which caller must free().
// If 'force' set, forces reload even if file size/time didn't change.
//
// Returns:
// 0 -- file unchanged or not editing
// 1 -- file changed, internal records updated, 'code' has new content
// -1 -- error getting file info (strerror() has reason)
//
int ExternalCodeEditor::handle_changes(const char **code, int force) {
code[0] = 0;
if ( !is_editing() ) return 0;
// Get current time/size info, see if file changed
int changed = 0;
{
struct stat sbuf;
if ( stat(filename(), &sbuf) < 0 ) return(-1); // TODO: show fl_alert(), do this in win32 too, adjust func call docs above
time_t now_mtime = sbuf.st_mtime;
size_t now_size = sbuf.st_size;
// OK, now see if file changed; update records if so
if ( now_mtime != file_mtime_ ) { changed = 1; file_mtime_ = now_mtime; }
if ( now_size != file_size_ ) { changed = 1; file_size_ = now_size; }
}
// No changes? done
if ( !changed && !force ) return 0;
// Changes? Load file, and fallthru to close()
int fd = open(filename(), O_RDONLY);
if ( fd < 0 ) {
fl_alert("ERROR: can't open '%s': %s", filename(), strerror(errno));
return -1;
}
int ret = 0;
char *buf = (char*)malloc(file_size_ + 1);
ssize_t count = read(fd, buf, file_size_);
if ( count == -1 ) {
fl_alert("ERROR: read() %s: %s", filename(), strerror(errno));
free((void*)buf);
ret = -1;
} else if ( (long)count != (long)file_size_ ) {
fl_alert("ERROR: read() failed for %s:\n"
"expected %ld bytes, only got %ld",
filename(), long(file_size_), long(count));
ret = -1;
} else {
// Success -- file loaded OK
buf[count] = '\0';
code[0] = buf; // return pointer to allocated buffer
ret = 1;
}
close(fd);
return ret;
}
// [Public] Remove the tmp file (if it exists), and zero out filename/mtime/size
// Returns:
// -1 -- on error (dialog is posted as to why)
// 0 -- no file to remove
// 1 -- file was removed
//
int ExternalCodeEditor::remove_tmpfile() {
const char *tmpfile = filename();
if ( !tmpfile ) return 0;
// Filename set? remove (if exists) and zero filename/mtime/size
if ( is_file(tmpfile) ) {
if ( G_debug ) printf("Removing tmpfile '%s'\n", tmpfile);
if ( remove(tmpfile) < 0 ) {
fl_alert("WARNING: Can't remove() '%s': %s", tmpfile, strerror(errno));
return -1;
}
}
set_filename(0);
file_mtime_ = 0;
file_size_ = 0;
return 1;
}
// [Static/Public] Return tmpdir name for this fluid instance.
// Returns pointer to static memory.
//
const char* ExternalCodeEditor::tmpdir_name() {
static char dirname[100];
snprintf(dirname, sizeof(dirname), "/tmp/.fluid-%ld", (long)getpid());
return dirname;
}
// [Static/Public] Clear the external editor's tempdir
// Static so that the main program can call it on exit to clean up.
//
void ExternalCodeEditor::tmpdir_clear() {
const char *tmpdir = tmpdir_name();
if ( is_dir(tmpdir) ) {
if ( G_debug ) printf("Removing tmpdir '%s'\n", tmpdir);
if ( rmdir(tmpdir) < 0 ) {
fl_alert("WARNING: Can't rmdir() '%s': %s", tmpdir, strerror(errno));
}
}
}
// [Protected] Creates temp dir (if doesn't exist) and returns the dirname
// as a static string. Returns NULL on error, dialog shows reason.
//
const char* ExternalCodeEditor::create_tmpdir() {
const char *dirname = tmpdir_name();
if ( ! is_dir(dirname) ) {
if ( mkdir(dirname, 0777) < 0 ) {
fl_alert("can't create directory '%s': %s",
dirname, strerror(errno));
return NULL;
}
}
return dirname;
}
// [Protected] Returns temp filename in static buffer.
// Returns NULL if can't, posts dialog explaining why.
//
const char* ExternalCodeEditor::tmp_filename() {
static char path[512];
const char *tmpdir = create_tmpdir();
if ( !tmpdir ) return 0;
extern const char *code_file_name; // fluid's global
const char *ext = code_file_name; // e.g. ".cxx"
snprintf(path, sizeof(path), "%s/%p%s", tmpdir, (void*)this, ext);
path[sizeof(path)-1] = 0;
return path;
}
// [Static/Local] Save string 'code' to 'filename', returning file's mtime/size
// 'code' can be NULL -- writes an empty file if so.
// Returns:
// 0 on success
// -1 on error (posts dialog with reason)
//
static int save_file(const char *filename, const char *code) {
int fd = open(filename, O_WRONLY|O_CREAT, 0666);
if ( fd == -1 ) {
fl_alert("ERROR: open() '%s': %s", filename, strerror(errno));
return -1;
}
ssize_t clen = strlen(code);
ssize_t count = write(fd, code, clen);
int ret = 0;
if ( count == -1 ) {
fl_alert("ERROR: write() '%s': %s", filename, strerror(errno));
ret = -1; // fallthru to close()
} else if ( count != clen ) {
fl_alert("ERROR: write() '%s': wrote only %lu bytes, expected %lu",
filename, (unsigned long)count, (unsigned long)clen);
ret = -1; // fallthru to close()
}
close(fd);
return(ret);
}
// [Static/Local] Convert string 's' to array of argv[], useful for execve()
// o 's' will be modified (words will be NULL separated)
// o argv[] will end up pointing to the words of 's'
// o Caller must free argv with: free(argv);
//
static int make_args(char *s, // string containing words (gets trashed!)
int *aargc, // pointer to argc
char ***aargv) { // pointer to argv
char *ss, **argv;
if ((argv=(char**)malloc(sizeof(char*) * (strlen(s)/2)))==NULL) {
return -1;
}
int t;
for(t=0; (t==0)?(ss=strtok(s," \t")):(ss=strtok(0," \t")); t++) {
argv[t] = ss;
}
argv[t] = 0;
aargv[0] = argv;
aargc[0] = t;
return(t);
}
// [Protected] Start editor in background (fork/exec)
// Returns:
// > 0 on success, leaves editor child process running as 'pid_'
// > -1 on error, posts dialog with reason (child exits)
//
int ExternalCodeEditor::start_editor(const char *editor_cmd,
const char *filename) {
if ( G_debug ) printf("start_editor() cmd='%s', filename='%s'\n",
editor_cmd, filename);
char cmd[1024];
snprintf(cmd, sizeof(cmd), "%s %s", editor_cmd, filename);
// Fork editor to background..
switch ( pid_ = fork() ) {
case -1: // error
fl_alert("couldn't fork(): %s", strerror(errno));
return -1;
case 0: { // child
// NOTE: OSX wants minimal code between fork/exec, see Apple TN2083
int nargs;
char **args = 0;
make_args(cmd, &nargs, &args);
execvp(args[0], args); // run command - doesn't return if succeeds
fl_alert("couldn't exec() '%s': %s", cmd, strerror(errno));
exit(1);
}
default: // parent
if ( L_editors_open++ == 0 ) // first editor? start timers
{ start_update_timer(); }
if ( G_debug )
printf("--- EDITOR STARTED: pid_=%ld #open=%d\n", (long)pid_, L_editors_open);
break;
}
return 0;
}
// [Public] Try to reap external editor process
// Returns:
// -2 -- editor not open
// -1 -- waitpid() failed (errno has reason)
// 0 -- process still running
// >0 -- process finished + reaped (value is pid)
// Handles removing tmpfile/zeroing file_mtime/file_size
//
pid_t ExternalCodeEditor::reap_editor() {
if ( !is_editing() ) return -2;
int status = 0;
pid_t wpid;
switch (wpid = waitpid(pid_, &status, WNOHANG)) {
case -1: // waitpid() failed
return -1;
case 0: // process didn't reap, still running
return 0;
default: // process reaped
remove_tmpfile(); // also zeroes mtime/size
pid_ = -1;
if ( --L_editors_open <= 0 )
{ stop_update_timer(); }
break;
}
if ( G_debug )
printf("*** EDITOR REAPED: pid=%ld #open=%d\n", long(wpid), L_editors_open);
return wpid;
}
// [Public] Open external editor using 'editor_cmd' to edit 'code'
// 'code' contains multiline code to be edited as a temp file.
//
// Returns:
// 0 if succeeds
// -1 if can't open editor (already open, etc),
// errors were shown to user in a dialog
//
int ExternalCodeEditor::open_editor(const char *editor_cmd,
const char *code) {
// Make sure a temp filename exists
if ( !filename() ) {
set_filename(tmp_filename());
if ( !filename() ) return -1;
}
// See if tmpfile already exists or editor already open
if ( is_file(filename()) ) {
if ( is_editing() ) {
// See if editor recently closed but not reaped; try to reap
pid_t wpid = reap_editor();
switch (wpid) {
case -1: // waitpid() failed
fl_alert("ERROR: waitpid() failed: %s\nfile='%s', pid=%ld",
strerror(errno), filename(), (long)pid_);
return -1;
case 0: // process still running
fl_alert("Editor Already Open\n file='%s'\n pid=%ld",
filename(), (long)pid_);
return 0;
default: // process reaped, wpid is pid reaped
if ( G_debug )
printf("*** REAPED EXTERNAL EDITOR: PID %ld\n", (long)wpid);
break; // fall thru to open new editor instance
}
// Reinstate tmp filename (reap_editor() clears it)
set_filename(tmp_filename());
}
}
if ( save_file(filename(), code) < 0 ) {
return -1; // errors were shown in dialog
}
// Update mtime/size from closed file
struct stat sbuf;
if ( stat(filename(), &sbuf) < 0 ) {
fl_alert("ERROR: can't stat('%s'): %s", filename(), strerror(errno));
return -1;
}
file_mtime_ = sbuf.st_mtime;
file_size_ = sbuf.st_size;
if ( start_editor(editor_cmd, filename()) < 0 ) { // open file in external editor
if ( G_debug ) printf("Editor failed to start\n");
return -1; // errors were shown in dialog
}
return 0;
}
// [Public/Static] Start update timer
void ExternalCodeEditor::start_update_timer() {
if ( !L_update_timer_cb ) return;
if ( G_debug ) printf("--- TIMER: STARTING UPDATES\n");
Fl::add_timeout(2.0, L_update_timer_cb);
}
// [Public/Static] Stop update timer
void ExternalCodeEditor::stop_update_timer() {
if ( !L_update_timer_cb ) return;
if ( G_debug ) printf("--- TIMER: STOPPING UPDATES\n");
Fl::remove_timeout(L_update_timer_cb);
}
// [Public/Static] Set app's external editor update timer callback
// This is the app's callback callback we start while editors are open,
// and stop when all editors are closed.
//
void ExternalCodeEditor::set_update_timer_callback(Fl_Timeout_Handler cb) {
L_update_timer_cb = cb;
}
// [Static/Public] See if any external editors are open.
// App's timer cb can see if any editors need checking..
//
int ExternalCodeEditor::editors_open() {
return L_editors_open;
}
#endif /* !WIN32 */
//
// End of "$Id: ExternalCodeEditor_UNIX.cxx 11878 2016-08-16 20:42:22Z greg.ercolano $".
//