aboutsummaryrefslogtreecommitdiffstats
path: root/erts/etc/unix/to_erl.c
diff options
context:
space:
mode:
Diffstat (limited to 'erts/etc/unix/to_erl.c')
-rw-r--r--erts/etc/unix/to_erl.c610
1 files changed, 610 insertions, 0 deletions
diff --git a/erts/etc/unix/to_erl.c b/erts/etc/unix/to_erl.c
new file mode 100644
index 0000000000..588d127445
--- /dev/null
+++ b/erts/etc/unix/to_erl.c
@@ -0,0 +1,610 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 1996-2009. All Rights Reserved.
+ *
+ * The contents of this file are subject to the Erlang Public License,
+ * Version 1.1, (the "License"); you may not use this file except in
+ * compliance with the License. You should have received a copy of the
+ * Erlang Public License along with this software. If not, it can be
+ * retrieved online at http://www.erlang.org/.
+ *
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * %CopyrightEnd%
+ */
+/*
+ * Module: to_erl.c
+ *
+ * This module implements a process that opens two specified FIFOs, one
+ * for reading and one for writing; reads from its stdin, and writes what
+ * it has read to the write FIF0; reads from the read FIFO, and writes to
+ * its stdout.
+ *
+ ________ _________
+ | |--<-- pipe.r (fifo1) --<--| |
+ | to_erl | | run_erl | (parent)
+ |________|-->-- pipe.w (fifo2) -->--|_________|
+ ^ master pty
+ |
+ | slave pty
+ ____V____
+ | |
+ | "erl" | (child)
+ |_________|
+ */
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <termios.h>
+#include <dirent.h>
+#include <signal.h>
+#include <errno.h>
+#ifdef HAVE_SYS_IOCTL_H
+# include <sys/ioctl.h>
+#endif
+
+#include "run_erl.h"
+#include "safe_string.h" /* strn_cpy, strn_catf, sn_printf, etc. */
+
+#if defined(O_NONBLOCK)
+# define DONT_BLOCK_PLEASE O_NONBLOCK
+#else
+# define DONT_BLOCK_PLEASE O_NDELAY
+# if !defined(EAGAIN)
+# define EAGAIN -3898734
+# endif
+#endif
+
+#ifdef HAVE_STRERROR
+# define STRERROR(x) strerror(x)
+#else
+# define STRERROR(x) ""
+#endif
+
+#define noDEBUG
+
+#define PIPE_DIR "/tmp/"
+#define PIPE_STUBNAME "erlang.pipe"
+#define PIPE_STUBLEN strlen(PIPE_STUBNAME)
+
+#ifdef DEBUG
+#define STATUS(s) { fprintf(stderr, (s)); fflush(stderr); }
+#else
+#define STATUS(s)
+#endif
+
+#ifndef FILENAME_MAX
+#define FILENAME_MAX 250
+#endif
+
+static struct termios tty_smode, tty_rmode;
+static int tty_eof = 0;
+static int recv_sig = 0;
+static int protocol_ver = RUN_ERL_LO_VER; /* assume lowest to begin with */
+
+static int write_all(int fd, const char* buf, int len);
+static int window_size_seq(char* buf, size_t bufsz);
+static int version_handshake(char* buf, int len, int wfd);
+#ifdef DEBUG
+static void show_terminal_settings(struct termios *);
+#endif
+
+static void handle_ctrlc(int sig)
+{
+ /* Reinstall the handler, and signal break flag */
+ signal(SIGINT,handle_ctrlc);
+ recv_sig = SIGINT;
+}
+
+static void handle_sigwinch(int sig)
+{
+ recv_sig = SIGWINCH;
+}
+
+static void usage(char *pname)
+{
+ fprintf(stderr, "Usage: %s [-h|-F] [pipe_name|pipe_dir/]\n", pname);
+ fprintf(stderr, "\t-h\tThis help text.\n");
+ fprintf(stderr, "\t-F\tForce connection even though pipe is locked by other to_erl process.\n");
+}
+
+int main(int argc, char **argv)
+{
+ char FIFO1[FILENAME_MAX], FIFO2[FILENAME_MAX];
+ int i, len, wfd, rfd, result = 0;
+ fd_set readfds;
+ char buf[BUFSIZ];
+ char pipename[FILENAME_MAX];
+ int pipeIx = 1;
+ int force_lock = 0;
+ int got_some = 0;
+
+ if (argc >= 2 && argv[1][0]=='-') {
+ switch (argv[1][1]) {
+ case 'h':
+ usage(argv[0]);
+ exit(1);
+ case 'F':
+ force_lock = 1;
+ break;
+ default:
+ fprintf(stderr,"Invalid option '%s'\n",argv[1]);
+ exit(1);
+ }
+ pipeIx = 2;
+ }
+
+#ifdef DEBUG
+ fprintf(stderr, "%s: pid is : %d\n", argv[0], (int)getpid());
+#endif
+
+ strn_cpy(pipename, sizeof(pipename),
+ (argv[pipeIx] ? argv[pipeIx] : PIPE_DIR));
+
+ if(*pipename && pipename[strlen(pipename)-1] == '/') {
+ /* The user wishes us to find a pipe name in the specified */
+ /* directory */
+ int highest_pipe_num = 0;
+ DIR *dirp;
+ struct dirent *direntp;
+
+ dirp = opendir(pipename);
+ if(!dirp) {
+ fprintf(stderr, "Can't access pipe directory %s.\n", pipename);
+ exit(1);
+ }
+
+ /* Check the directory for existing pipes */
+
+ while((direntp=readdir(dirp)) != NULL) {
+ if(strncmp(direntp->d_name,PIPE_STUBNAME,PIPE_STUBLEN)==0) {
+ int num = atoi(direntp->d_name+PIPE_STUBLEN+1);
+ if(num > highest_pipe_num)
+ highest_pipe_num = num;
+ }
+ }
+ closedir(dirp);
+ strn_catf(pipename, sizeof(pipename), (highest_pipe_num?"%s.%d":"%s"),
+ PIPE_STUBNAME, highest_pipe_num);
+ } /* if */
+
+ /* read FIFO */
+ sn_printf(FIFO1,sizeof(FIFO1),"%s.r",pipename);
+ /* write FIFO */
+ sn_printf(FIFO2,sizeof(FIFO2),"%s.w",pipename);
+
+ /* Check that nobody is running to_erl on this pipe already */
+ if ((wfd = open (FIFO1, O_WRONLY|DONT_BLOCK_PLEASE, 0)) >= 0) {
+ /* Open as server succeeded -- to_erl is already running! */
+ close(wfd);
+ fprintf(stderr, "Another to_erl process already attached to pipe "
+ "%s.\n", pipename);
+ if (force_lock) {
+ fprintf(stderr, "But we proceed anyway by force (-F).\n");
+ }
+ else {
+ exit(1);
+ }
+ }
+
+ if ((rfd = open (FIFO1, O_RDONLY|DONT_BLOCK_PLEASE, 0)) < 0) {
+#ifdef DEBUG
+ fprintf(stderr, "Could not open FIFO %s for reading.\n", FIFO1);
+#endif
+ fprintf(stderr, "No running Erlang on pipe %s.\n", pipename);
+ exit(1);
+ }
+#ifdef DEBUG
+ fprintf(stderr, "to_erl: %s opened for reading\n", FIFO1);
+#endif
+
+ if ((wfd = open (FIFO2, O_WRONLY|DONT_BLOCK_PLEASE, 0)) < 0) {
+#ifdef DEBUG
+ fprintf(stderr, "Could not open FIFO %s for writing.\n", FIFO2);
+#endif
+ fprintf(stderr, "No running Erlang on pipe %s.\n", pipename);
+ close(rfd);
+ exit(1);
+ }
+#ifdef DEBUG
+ fprintf(stderr, "to_erl: %s opened for writing\n", FIFO2);
+#endif
+
+ fprintf(stderr, "Attaching to %s (^D to exit)\n\n", pipename);
+
+ /* Set break handler to our handler */
+ signal(SIGINT,handle_ctrlc);
+
+ /*
+ * Save the current state of the terminal, and set raw mode.
+ */
+ if (tcgetattr(0, &tty_rmode) , 0) {
+ fprintf(stderr, "Cannot get terminals current mode\n");
+ exit(-1);
+ }
+ tty_smode = tty_rmode;
+ tty_eof = '\004'; /* Ctrl+D to exit */
+#ifdef DEBUG
+ show_terminal_settings(&tty_rmode);
+#endif
+ tty_smode.c_iflag =
+ 1*BRKINT |/*Signal interrupt on break.*/
+ 1*IGNPAR |/*Ignore characters with parity errors.*/
+ 1*ISTRIP |/*Strip character.*/
+ 0;
+
+#if 0
+0*IGNBRK |/*Ignore break condition.*/
+0*PARMRK |/*Mark parity errors.*/
+0*INPCK |/*Enable input parity check.*/
+0*INLCR |/*Map NL to CR on input.*/
+0*IGNCR |/*Ignore CR.*/
+0*ICRNL |/*Map CR to NL on input.*/
+0*IUCLC |/*Map upper-case to lower-case on input.*/
+0*IXON |/*Enable start/stop output control.*/
+0*IXANY |/*Enable any character to restart output.*/
+0*IXOFF |/*Enable start/stop input control.*/
+0*IMAXBEL|/*Echo BEL on input line too long.*/
+#endif
+
+ tty_smode.c_oflag =
+ 1*OPOST |/*Post-process output.*/
+ 1*ONLCR |/*Map NL to CR-NL on output.*/
+#ifdef XTABS
+ 1*XTABS |/*Expand tabs to spaces. (Linux)*/
+#endif
+#ifdef OXTABS
+ 1*OXTABS |/*Expand tabs to spaces. (FreeBSD)*/
+#endif
+#ifdef NL0
+ 1*NL0 |/*Select newline delays*/
+#endif
+#ifdef CR0
+ 1*CR0 |/*Select carriage-return delays*/
+#endif
+#ifdef TAB0
+ 1*TAB0 |/*Select horizontal tab delays*/
+#endif
+#ifdef BS0
+ 1*BS0 |/*Select backspace delays*/
+#endif
+#ifdef VT0
+ 1*VT0 |/*Select vertical tab delays*/
+#endif
+#ifdef FF0
+ 1*FF0 |/*Select form feed delays*/
+#endif
+ 0;
+
+#if 0
+0*OLCUC |/*Map lower case to upper on output.*/
+0*OCRNL |/*Map CR to NL on output.*/
+0*ONOCR |/*No CR output at column 0.*/
+0*ONLRET |/*NL performs CR function.*/
+0*OFILL |/*Use fill characters for delay.*/
+0*OFDEL |/*Fill is DEL, else NULL.*/
+0*NL1 |
+0*CR1 |
+0*CR2 |
+0*CR3 |
+0*TAB1 |
+0*TAB2 |
+0*TAB3 |/*Expand tabs to spaces.*/
+0*BS1 |
+0*VT1 |
+0*FF1 |
+#endif
+
+ /* JALI: removed setting the tty_smode.c_cflag flags, since this is not */
+ /* advisable if this is a *real* terminal, such as the console. In fact */
+ /* this may hang the entire machine, deep, deep down (signalling break */
+ /* or toggling the abort switch doesn't help) */
+
+ tty_smode.c_lflag =
+ 0;
+
+#if 0
+0*ISIG |/*Enable signals.*/
+0*ICANON |/*Canonical input (erase and kill processing).*/
+0*XCASE |/*Canonical upper/lower presentation.*/
+0*ECHO |/*Enable echo.*/
+0*ECHOE |/*Echo erase character as BS-SP-BS.*/
+0*ECHOK |/*Echo NL after kill character.*/
+0*ECHONL |/*Echo NL.*/
+0*NOFLSH |/*Disable flush after interrupt or quit.*/
+0*TOSTOP |/*Send SIGTTOU for background output.*/
+0*ECHOCTL|/*Echo control characters as ^char, delete as ^?.*/
+0*ECHOPRT|/*Echo erase character as character erased.*/
+0*ECHOKE |/*BS-SP-BS erase entire line on line kill.*/
+0*FLUSHO |/*Output is being flushed.*/
+0*PENDIN |/*Retype pending input at next read or input character.*/
+0*IEXTEN |/*Enable extended (implementation-defined) functions.*/
+#endif
+
+ tty_smode.c_cc[VMIN] =0;/* Note that VMIN is the same as VEOF! */
+ tty_smode.c_cc[VTIME] =0;/* Note that VTIME is the same as VEOL! */
+ tty_smode.c_cc[VINTR] =3;
+
+ tcsetattr(0, TCSANOW, &tty_smode);
+
+#ifdef DEBUG
+ show_terminal_settings(&tty_smode);
+#endif
+ /*
+ * "Write a ^R to the FIFO which causes the other end to redisplay
+ * the input line."
+ * This does not seem to work as was intended in old comment above.
+ * However, this control character is now (R12B-3) used by run_erl
+ * to trigger the version handshaking between to_erl and run_erl
+ * at the start of every new to_erl-session.
+ */
+ write(wfd, "\022", 1);
+
+ /*
+ * read and write
+ */
+ while (1) {
+ FD_ZERO(&readfds);
+ FD_SET(0, &readfds);
+ FD_SET(rfd, &readfds);
+ if (select(rfd + 1, &readfds, NULL, NULL, NULL) < 0) {
+ if (recv_sig) {
+ FD_ZERO(&readfds);
+ }
+ else {
+ fprintf(stderr, "Error in select.\n");
+ result = -1;
+ break;
+ }
+ }
+ len = 0;
+
+ /*
+ * Read from terminal and write to FIFO
+ */
+ if (recv_sig) {
+ switch (recv_sig) {
+ case SIGINT:
+ fprintf(stderr, "[Break]\n\r");
+ buf[0] = '\003';
+ len = 1;
+ break;
+ case SIGWINCH:
+ len = window_size_seq(buf,sizeof(buf));
+ break;
+ default:
+ fprintf(stderr,"Unexpected signal: %u\n",recv_sig);
+ }
+ recv_sig = 0;
+ }
+ else if (FD_ISSET(0, &readfds)) {
+ len = read(0, buf, sizeof(buf));
+ if (len <= 0) {
+ close(rfd);
+ close(wfd);
+ if (len < 0) {
+ fprintf(stderr, "Error in reading from stdin.\n");
+ result = -1;
+ } else {
+ fprintf(stderr, "[EOF]\n\r");
+ }
+ break;
+ }
+ /* check if there is an eof character in input */
+ for (i = 0; i < len && buf[i] != tty_eof; i++);
+ if (buf[i] == tty_eof) {
+ fprintf(stderr, "[Quit]\n\r");
+ break;
+ }
+ }
+
+ if (len) {
+#ifdef DEBUG
+ write(1, buf, len);
+#endif
+ if (write_all(wfd, buf, len) != len) {
+ fprintf(stderr, "Error in writing to FIFO.\n");
+ close(rfd);
+ close(wfd);
+ result = -1;
+ break;
+ }
+ STATUS("\" OK\r\n");
+ }
+
+ /*
+ * Read from FIFO, write to terminal.
+ */
+ if (FD_ISSET(rfd, &readfds)) {
+ STATUS("FIFO read: ");
+ len = read(rfd, buf, BUFSIZ);
+ if (len < 0 && errno == EAGAIN) {
+ /*
+ * No data this time, but the writing end of the FIFO is still open.
+ * Do nothing.
+ */
+ ;
+ } else if (len <= 0) {
+ /*
+ * Either an error or end of file. In either case, break out
+ * of the loop.
+ */
+ close(rfd);
+ close(wfd);
+ if (len < 0) {
+ fprintf(stderr, "Error in reading from FIFO.\n");
+ result = -1;
+ } else
+ fprintf(stderr, "[End]\n\r");
+ break;
+ } else {
+ if (!got_some) {
+ if ((len=version_handshake(buf,len,wfd)) < 0) {
+ close(rfd);
+ close(wfd);
+ result = -1;
+ break;
+ }
+ if (protocol_ver >= 1) {
+ /* Tell run_erl size of terminal window */
+ signal(SIGWINCH, handle_sigwinch);
+ raise(SIGWINCH);
+ }
+ got_some = 1;
+ }
+
+ /*
+ * We successfully read at least one character. Write what we got.
+ */
+ STATUS("Terminal write: \"");
+ if (write_all(1, buf, len) != len) {
+ fprintf(stderr, "Error in writing to terminal.\n");
+ close(rfd);
+ close(wfd);
+ result = -1;
+ break;
+ }
+ STATUS("\" OK\r\n");
+ }
+ }
+ }
+
+ /*
+ * Reset terminal characterstics
+ * XXX
+ */
+ tcsetattr(0, TCSANOW, &tty_rmode);
+ return 0;
+}
+
+/* Call write() until entire buffer has been written or error.
+ * Return len or -1.
+ */
+static int write_all(int fd, const char* buf, int len)
+{
+ int left = len;
+ int written;
+ while (left) {
+ written = write(fd,buf,left);
+ if (written < 0) {
+ return -1;
+ }
+ left -= written;
+ buf += written;
+ }
+ return len;
+}
+
+static int window_size_seq(char* buf, size_t bufsz)
+{
+#ifdef TIOCGWINSZ
+ struct winsize ws;
+ static const char prefix[] = "\033_";
+ static const char suffix[] = "\033\\";
+ /* This Esc sequence is called "Application Program Command"
+ and seems suitable to use for our own customized stuff. */
+
+ if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) == 0) {
+ int len = sn_printf(buf, bufsz, "%swinsize=%u,%u%s",
+ prefix, ws.ws_col, ws.ws_row, suffix);
+ return len;
+ }
+#endif /* TIOCGWINSZ */
+ return 0;
+}
+
+/* to_erl run_erl
+ * | |
+ * |---------- '\022' -------->| (session start)
+ * | |
+ * |<---- "[run_erl v1-0]" ----| (version interval)
+ * | |
+ * |--- Esc_"version=1"Esc\ -->| (common version)
+ * | |
+ */
+static int version_handshake(char* buf, int len, int wfd)
+{
+ unsigned re_high=0, re_low;
+ char *end = find_str(buf,len,"]\n");
+
+ if (end && sscanf(buf,"[run_erl v%u-%u",&re_high,&re_low)==2) {
+ char wbuf[30];
+ int wlen;
+
+ if (re_low > RUN_ERL_HI_VER || re_high < RUN_ERL_LO_VER) {
+ fprintf(stderr,"Incompatible versions: to_erl=v%u-%u run_erl=v%u-%u\n",
+ RUN_ERL_HI_VER, RUN_ERL_LO_VER, re_high, re_low);
+ return -1;
+ }
+ /* Choose highest common version */
+ protocol_ver = re_high < RUN_ERL_HI_VER ? re_high : RUN_ERL_HI_VER;
+
+ wlen = sn_printf(wbuf, sizeof(wbuf), "\033_version=%u\033\\",
+ protocol_ver);
+ if (write_all(wfd, wbuf, wlen) < 0) {
+ fprintf(stderr,"Failed to send version handshake\n");
+ return -1;
+ }
+ end += 2;
+ len -= (end-buf);
+ memmove(buf,end,len);
+
+ }
+ else { /* we assume old run_erl without version handshake */
+ protocol_ver = 0;
+ }
+
+ if (re_high != RUN_ERL_HI_VER) {
+ fprintf(stderr,"run_erl has different version, "
+ "using common protocol level %u\n", protocol_ver);
+ }
+
+ return len;
+}
+
+
+#ifdef DEBUG
+#define S(x) ((x) > 0 ? 1 : 0)
+
+static void show_terminal_settings(struct termios *t)
+{
+ fprintf(stderr,"c_iflag:\n");
+ fprintf(stderr,"Signal interrupt on break: BRKINT %d\n", S(t->c_iflag & BRKINT));
+ fprintf(stderr,"Map CR to NL on input: ICRNL %d\n", S(t->c_iflag & ICRNL));
+ fprintf(stderr,"Ignore break condition: IGNBRK %d\n", S(t->c_iflag & IGNBRK));
+ fprintf(stderr,"Ignore CR: IGNCR %d\n", S(t->c_iflag & IGNCR));
+ fprintf(stderr,"Ignore char with par. err's: IGNPAR %d\n", S(t->c_iflag & IGNPAR));
+ fprintf(stderr,"Map NL to CR on input: INLCR %d\n", S(t->c_iflag & INLCR));
+ fprintf(stderr,"Enable input parity check: INPCK %d\n", S(t->c_iflag & INPCK));
+ fprintf(stderr,"Strip character ISTRIP %d\n", S(t->c_iflag & ISTRIP));
+ fprintf(stderr,"Enable start/stop input ctrl IXOFF %d\n", S(t->c_iflag & IXOFF));
+ fprintf(stderr,"ditto output ctrl IXON %d\n", S(t->c_iflag & IXON));
+ fprintf(stderr,"Mark parity errors PARMRK %d\n", S(t->c_iflag & PARMRK));
+ fprintf(stderr,"\n");
+ fprintf(stderr,"c_oflag:\n");
+ fprintf(stderr,"Perform output processing OPOST %d\n", S(t->c_oflag & OPOST));
+ fprintf(stderr,"\n");
+ fprintf(stderr,"c_cflag:\n");
+ fprintf(stderr,"Ignore modem status lines CLOCAL %d\n", S(t->c_cflag & CLOCAL));
+ fprintf(stderr,"\n");
+ fprintf(stderr,"c_local:\n");
+ fprintf(stderr,"Enable echo ECHO %d\n", S(t->c_lflag & ECHO));
+ fprintf(stderr,"\n");
+ fprintf(stderr,"c_cc:\n");
+ fprintf(stderr,"c_cc[VEOF] %d\n", t->c_cc[VEOF]);
+}
+#endif