fix(EINTR): retry operations on interrupt

src/command.c

@@ -320,10 +320,18 @@ struct Value *handle_lcd_command(String *args, int offset)
     }
 
 #if HAVE_GETCWD
-    oprintf("%% Current directory is %s", getcwd(buffer, PATH_MAX));
+    if (!getcwd(buffer, sizeof(buffer))) {
+	operror("getcwd");
+	return shareval(val_zero);
+    }
+    oprintf("%% Current directory is %s", buffer);
 #else
 # if HAVE_GETWD
-    oprintf("%% Current directory is %s", getwd(buffer));
+    if (!getwd(buffer)) {
+	operror("getwd");
+	return shareval(val_zero);
+    }
+    oprintf("%% Current directory is %s", buffer);
 # endif
 #endif
     return shareval(val_one);
@@ -359,8 +367,11 @@ int handle_echo_func(
             return 0;
     }
     if (raw) {
-        write(STDOUT_FILENO, src->data, src->len);
-        return 1;
+	if (write_full(STDOUT_FILENO, src->data, src->len) < 0) {
+	    operror("write");
+	    return 0;
+	}
+	return 1;
     }
 
     newstr = inline_flag ? CS(decode_attr(src, 0, 0)) : CS(Stringdup(src));
@@ -823,4 +834,3 @@ struct Value *handle_bind_command(String *args, int offset)
     return newint(add_new_macro(NULL, print_to_ascii(NULL, pattern)->data,
 	NULL, NULL, body, 1, 100, 0, FALSE, 0));
 }
-

src/output.c

@@ -349,8 +349,12 @@ void bufflush(void)
 	n = outbuf->len - written;
 	if (n > 2048)
 	    n = 2048;
-        result = write(STDOUT_FILENO, outbuf->data + written, n);
-	if (result < 0) break;
+	RETRY_ON_EINTR(result, write(STDOUT_FILENO,
+				     outbuf->data + written, n));
+	if (result < 0)
+	    break;
+	if (result == 0)
+	    break;
 	written += result;
     }
     Stringtrunc(outbuf, 0);

src/port.h

@@ -79,6 +79,11 @@ extern int errno;  /* Some systems don't declare errno in errno.h. Duh. */
 
 #include <stdio.h>
 
+#define RETRY_ON_EINTR(result, expr) \
+    do {                             \
+	(result) = (expr);           \
+    } while ((result) == -1 && errno == EINTR)
+
 #ifndef SEEK_SET
 # define SEEK_SET 0
 #endif

src/signals.c

@@ -434,9 +434,11 @@ void init_exename(char *name)
 {
     argv0 = name;
 #if HAVE_GETCWD
-    getcwd(initial_dir, PATH_MAX);
+    if (!getcwd(initial_dir, sizeof(initial_dir)))
+	initial_dir[0] = '\0';
 #elif HAVE_GETWD
-    getwd(initial_dir);
+    if (!getwd(initial_dir))
+	initial_dir[0] = '\0';
 #endif
     initial_path = getenv("PATH");
 }

src/socket.c

@@ -342,6 +342,9 @@ static Sock *find_sock(const char *name);
 static void  wload(World *w);
 static int   fg_sock(Sock *sock, int quiet);
 static int   get_host_address(Sock *sock, const char **what, int *errp);
+#ifdef NONBLOCKING_GETHOST
+static void close_resolver(Sock *sock);
+#endif
 #if !HAVE_GETADDRINFO
 static int   tfgetaddrinfo(const char *nodename, const char *port,
 	     const struct addrinfo *hints, struct addrinfo **res);
@@ -1491,6 +1494,29 @@ static int ICONFAIL(Sock *sock, const char *what, const char *why)
     return 0;
 }
 
+#ifdef NONBLOCKING_GETHOST
+static void close_resolver(Sock *sock)
+{
+#ifdef PLATFORM_UNIX
+    pid_t pid;
+#endif /* PLATFORM_UNIX */
+
+    if (sock->fd >= 0) {
+	close(sock->fd);
+	sock->fd = -1;
+    }
+#ifdef PLATFORM_UNIX
+    if (sock->pid >= 0) {
+	RETRY_ON_EINTR(pid, waitpid(sock->pid, NULL, 0));
+	if (pid < 0)
+	    tfprintf(tferr, "waitpid %ld: %s", (long)sock->pid,
+		strerror(errno));
+	sock->pid = -1;
+    }
+#endif /* PLATFORM_UNIX */
+}
+#endif
+
 static int openconn(Sock *sock)
 {
     int flags;
@@ -1500,41 +1526,34 @@ static int openconn(Sock *sock)
     if (xsock->constate == SS_RESOLVING) {
 	nbgai_hdr_t info = { 0, 0 };
 	struct addrinfo *ai;
-        FD_CLR(xsock->fd, &readers);
-        if (read(xsock->fd, &info, sizeof(info)) < 0 || info.err != 0) {
-            if (!info.err)
-                CONFAIL(xsock, "read", strerror(errno));
-            else
-		CONFAILHP(xsock, gai_strerror(info.err));
-            if (xsock->fd >= 0) {
-                close(xsock->fd);
-                xsock->fd = -1;
-            }
-# ifdef PLATFORM_UNIX
-	    if (xsock->pid >= 0)
-		if (waitpid(xsock->pid, NULL, 0) < 0)
-		    tfprintf(tferr, "waitpid %ld: %s", xsock->pid, strerror(errno));
-	    xsock->pid = -1;
-# endif /* PLATFORM_UNIX */
-            killsock(xsock);
-            return 0;
-        }
+	FD_CLR(xsock->fd, &readers);
+	if (read_full(xsock->fd, (char *)&info, sizeof(info)) < 0) {
+	    CONFAIL(xsock, "read", strerror(errno));
+	    close_resolver(xsock);
+	    killsock(xsock);
+	    return 0;
+	}
+	if (info.err != 0) {
+	    CONFAILHP(xsock, gai_strerror(info.err));
+	    close_resolver(xsock);
+	    killsock(xsock);
+	    return 0;
+	}
 	if (info.size <= 0) { /* shouldn't happen */
 	    xsock->addrs = NULL;
 	} else {
 	    xsock->addrs = XMALLOC(info.size);
-	    read(xsock->fd, (char*)xsock->addrs, info.size);
+	    if (read_full(xsock->fd, (char *)xsock->addrs, info.size) < 0) {
+		CONFAIL(xsock, "read", strerror(errno));
+		FREE(xsock->addrs);
+		xsock->addrs = NULL;
+		close_resolver(xsock);
+		killsock(xsock);
+		return 0;
+	    }
 	}
-        if (xsock->fd >= 0) {
-            close(xsock->fd);
-        }
-# ifdef PLATFORM_UNIX
-        if (xsock->pid >= 0)
-            if (waitpid(xsock->pid, NULL, 0) < 0)
-               tfprintf(tferr, "waitpid: %ld: %s", xsock->pid, strerror(errno));
-        xsock->pid = -1;
-# endif /* PLATFORM_UNIX */
-        xsock->constate = SS_RESOLVED;
+	close_resolver(xsock);
+	xsock->constate = SS_RESOLVED;
 	for (ai = xsock->addrs; ai; ai = ai->ai_next) {
 	    ai->ai_addr = (struct sockaddr*)((char*)ai + sizeof(*ai));
 	    if (ai->ai_next != 0) {
@@ -1851,11 +1870,13 @@ static void waitforhostname(int fd, const char *name, const char *port)
 	    iov[niov].iov_len = ai->ai_addrlen;
 	    niov++;
 	}
-	writev(fd, iov, niov);
+	(void)writev_full(fd, iov, niov);
 	if (res) freeaddrinfo(res);
     } else {
 	hdr.size = 0;
-	write(fd, &hdr, sizeof(hdr));
+	iov[0].iov_base = (char *)&hdr;
+	iov[0].iov_len = sizeof(hdr);
+	(void)writev_full(fd, iov, 1);
     }
     close(fd);
 }
@@ -1954,9 +1975,13 @@ static int establish(Sock *sock)
             } else if ((ai_connect(xsock->fd, xsock->addr) < 0) &&
                 errno != EISCONN)
             {
-                read(xsock->fd, &ch, 1);   /* must fail */
-		return ICONFAIL(xsock, "nonblocking connect 2/read", strerror(errno));
-            }
+		int connect_err = errno;
+		if (read(xsock->fd, &ch, 1) < 0) /* must fail */
+		    return ICONFAIL(xsock, "nonblocking connect 2/read",
+				    strerror(errno));
+		return ICONFAIL(xsock, "nonblocking connect 2",
+				strerror(connect_err));
+	    }
         }
 #endif
         if (err != 0) {
@@ -2115,9 +2140,13 @@ static void killsock(Sock *sock)
 #ifdef NONBLOCKING_GETHOST
 # ifdef PLATFORM_UNIX
     if (sock->pid >= 0) {
+	pid_t pid;
+
         kill(sock->pid, SIGTERM);
-        if (waitpid(sock->pid, NULL, 0) < 0)
-            tfprintf(tferr, "waitpid: %ld: %s", sock->pid, strerror(errno));
+	RETRY_ON_EINTR(pid, waitpid(sock->pid, NULL, 0));
+        if (pid < 0)
+            tfprintf(tferr, "waitpid: %ld: %s", (long)sock->pid,
+		strerror(errno));
         sock->pid = -1;
     }
 # endif /* PLATFORM_UNIX */

src/tfio.c

@@ -788,11 +788,27 @@ char igetchar(void)
 {
     char c;
     fd_set readers;
+    int result;
 
-    FD_ZERO(&readers);
-    FD_SET(STDIN_FILENO, &readers);
-    while(select(1, &readers, NULL, NULL, NULL) <= 0);
-    read(STDIN_FILENO, &c, 1);
+    for (;;) {
+	FD_ZERO(&readers);
+	FD_SET(STDIN_FILENO, &readers);
+	result = select(STDIN_FILENO + 1, &readers, NULL, NULL, NULL);
+	if (result > 0)
+	    break;
+	if (result < 0) {
+	    if (errno == EINTR)
+		continue;
+	    operror("select");
+	    return '\0';
+	}
+    }
+    RETRY_ON_EINTR(result, read(STDIN_FILENO, &c, 1));
+    if (result != 1) {
+	if (result < 0)
+	    operror("read");
+	return '\0';
+    }
     return c;
 }
 
@@ -900,8 +916,11 @@ String *tfgetS(String *str, TFILE *file)
                 file->off = next;
             }
             file->off = 0;
-            file->len = read(fileno(file->u.fp), file->buf, sizeof(file->buf));
-        } while (file->len > 0);
+	    RETRY_ON_EINTR(file->len, read(fileno(file->u.fp), file->buf,
+					   sizeof(file->buf)));
+	    if (file->len < 0)
+		operror("read");
+	} while (file->len > 0);
 
         file->len = -1;  /* note eof */
         return str->len ? str : NULL;
@@ -1004,4 +1023,3 @@ struct Value *handle_liststreams_command(String *args, int offset)
 
     return newint(count);
 }
-

src/util.c

@@ -22,6 +22,7 @@
 #endif
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <sys/uio.h>
 #include <limits.h>
 #include "port.h"
 #include "tf.h"
@@ -81,6 +82,72 @@ struct feature features[] = {
 
 static void  free_maillist(void);
 
+int read_full(int fd, char *buf, size_t len)
+{
+    size_t off = 0;
+
+    while (off < len) {
+	ssize_t result;
+
+	RETRY_ON_EINTR(result, read(fd, buf + off, len - off));
+	if (result < 0)
+	    return -1;
+	if (result == 0) {
+	    errno = EIO;
+	    return -1;
+	}
+	off += result;
+    }
+    return 0;
+}
+
+int write_full(int fd, const char *buf, size_t len)
+{
+    size_t off = 0;
+
+    while (off < len) {
+	ssize_t result;
+
+	RETRY_ON_EINTR(result, write(fd, buf + off, len - off));
+	if (result < 0)
+	    return -1;
+	if (result == 0) {
+	    errno = EIO;
+	    return -1;
+	}
+	off += result;
+    }
+    return 0;
+}
+
+int writev_full(int fd, struct iovec *iov, int niov)
+{
+    while (niov > 0) {
+	ssize_t result;
+	size_t written;
+
+	RETRY_ON_EINTR(result, writev(fd, iov, niov));
+	if (result < 0)
+	    return -1;
+	if (result == 0) {
+	    errno = EIO;
+	    return -1;
+	}
+
+	written = result;
+	while (niov > 0 && written >= iov[0].iov_len) {
+	    written -= iov[0].iov_len;
+	    iov++;
+	    niov--;
+	}
+	if (niov > 0 && written > 0) {
+	    iov[0].iov_base = (char *)iov[0].iov_base + written;
+	    iov[0].iov_len -= written;
+	}
+    }
+    return 0;
+}
+
 #if !STDC_HEADERS
 int lcase(x) char x; { return is_upper(x) ? tolower(x) : x; }
 int ucase(x) char x; { return is_lower(x) ? toupper(x) : x; }

src/util.h

@@ -14,6 +14,8 @@ struct feature {
     const int *flag;
 };
 
+struct iovec;
+
 #undef CTRL
 /* convert to or from ctrl character */
 #define CTRL(c)  (ucase(c) ^ '@')
@@ -101,6 +103,10 @@ extern const conString* print_to_ascii(String *buf, const char *str);
 extern const conString* ascii_to_print(const char *str);
 extern char  *cstrchr(const char *s, int c);
 extern char  *estrchr(const char *s, int c, int e);
+extern int    read_full(int fd, char *buf, size_t len);
+extern int    write_full(int fd, const char *buf, size_t len);
+/* writev_full() mutates iov while advancing through partial writes. */
+extern int    writev_full(int fd, struct iovec *iov, int niov);
 extern int    numarg(const char **str);
 extern int    nullstrcmp(const char *s, const char *t);
 extern int    nullcstrcmp(const char *s, const char *t);