sob

commit 3bf4efd89a43d94ad46bdda31137a3bc9404ed8c
parent 32e1b3714fc4c84188673f668fca121b7c9e9256
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date:   Fri, 24 Oct 2014 21:35:06 +0000

rework read/write fd code, sleep when there are too much timeouts

Diffstat:
M
sob.c
 | 
114
+++++++++++++++++++++++++++++++++++++++++++++++++++++---------------------------

1 file changed, 76 insertions(+), 38 deletions(-)
diff --git a/sob.c b/sob.c
@@ -11,6 +11,7 @@
 #include <sys/select.h>
 #include <unistd.h>
 #include <termios.h>
+#include <time.h>
 #include <wchar.h>
 
 #include "arg.h"
@@ -60,8 +61,8 @@ static int    line_promptlen(void);
 static int    line_pipeto(char **);
 static int    line_wordpipeto(char **);
 
-static int    pipe_readline(int, int, char *,
-                            void (*)(const char *, size_t, size_t));
+static int    pipe_read(int, int, char *,
+                        void (*)(const char *, size_t, size_t));
 static int    pipe_cmd(char *[], char *,
                        void (*)(const char *, size_t, size_t));
 
@@ -75,6 +76,9 @@ static void   setup(void);
 static void   sighandler(int);
 static void   usage(void);
 
+static int    readfd(int, char *, size_t);
+static int    writefd(int, char *, size_t);
+
 static size_t colw(const char *, size_t);
 static int    nonspace(int c);
 static size_t utf8len(const char *);
@@ -547,7 +551,47 @@ line_copywordcursor(char *buf, size_t bufsiz)
 }
 
 static int
-pipe_readline(int fd_in, int fd_out, char *writestr,
+readfd(int fd, char *buf, size_t len) {
+	size_t r, i = 0;
+
+	while(len > 0) {
+		if((r = read(fd, &buf[i], len)) == -1) {
+			if(errno == EINTR)
+				continue;
+			if(errno == EWOULDBLOCK)
+				return i;
+			return -1;
+		} else if(r == 0) {
+			return i;
+		}
+		i += r;
+		len -= r;
+	}
+	return i;
+}
+
+static int
+writefd(int fd, char *buf, size_t len) {
+	size_t w, i = 0;
+
+	while(len > 0) {
+		if((w = write(fd, &buf[i], len)) == -1) {
+			if(errno == EINTR)
+				continue;
+			if(errno == EWOULDBLOCK)
+				return i;
+			return -1;
+		} else if(w == 0) {
+			return i;
+		}
+		i += w;
+		len -= w;
+	}
+	return i;
+}
+
+static int
+pipe_read(int fd_in, int fd_out, char *writestr,
 	void (*f)(const char *, size_t, size_t))
 {
 	char buf[PIPE_BUF];
@@ -576,35 +620,28 @@ pipe_readline(int fd_in, int fd_out, char *writestr,
 		else if(!r) /* timeout */
 			continue;
 
-		if(haswritten) {
-			if(FD_ISSET(fd_in, &fdr)) {
-				while(1) {
-					if((r = read(fd_in, buf, sizeof(buf))) == -1) {
-						if(errno == EINTR)
-							continue;
-						goto fini;
-					} else {
-						buf[r] = '\0';
-						total += r;
-						if(f)
-							f(buf, r, total);
-						if(!r) {
-							status = 0;
-							goto fini;
-						}
-					}
-				}
-			}
-		} else {
-			if(FD_ISSET(fd_out, &fdw)) {
-				/* write error */
-				if((w = write(fd_out, writestr, strlen(writestr))) == -1)
+		if(FD_ISSET(fd_in, &fdr) && haswritten) {
+			while(1) {
+				if((r = readfd(fd_in, buf, sizeof(buf))) <= 0)
 					goto fini;
-				close(fd_out); /* sends EOF */
-				fd_out = -1;
-				haswritten = 1;
+				if(!r) {
+					status = 0;
+					goto fini;
+				}
+				if(f) {
+					buf[r] = '\0';
+					total += r;
+					f(buf, r, total);
+				}
 			}
 		}
+		if(FD_ISSET(fd_out, &fdw)) {
+			if((w = writefd(fd_out, writestr, strlen(writestr))) == -1)
+				goto fini;
+			close(fd_out); /* sends EOF */
+			fd_out = -1;
+			haswritten = 1;
+		}
 	}
 fini:
 	if(fd_in != -1)
@@ -656,7 +693,7 @@ pipe_cmd(char *cmd[], char *writestr, void (*f)(const char *, size_t, size_t))
 		sa.sa_handler = SIG_IGN;
 		sigaction(SIGPIPE, &sa, NULL);
 
-		if(pipe_readline(cp[0], pc[1], writestr, f) == -1)
+		if(pipe_read(cp[0], pc[1], writestr, f) == -1)
 			return -1;
 	}
 	return 0;
@@ -812,6 +849,7 @@ static int
 run(void)
 {
 	struct timeval tv;
+	struct timespec ts;
 	fd_set fdr;
 	int r, status = -1;
 	unsigned char buf[BUFSIZ];
@@ -828,22 +866,22 @@ run(void)
 		tv.tv_sec = 0;
 		tv.tv_usec = 32000; /* 32 ms */
 
-		errno = 0;
 		if((r = select(STDIN_FILENO + 1, &fdr, NULL, NULL, &tv)) == -1) {
 			if(errno != EINTR)
-				goto fini; /* E_INTR can happen on SIGWINCH */
+				goto fini; /* E_INTR can happen on a signal like SIGWINCH */
 		} else if(!r) {
 			continue; /* timeout */
 		}
-
 		if(FD_ISSET(STDIN_FILENO, &fdr)) {
-			errno = 0;
-			if((r = read(STDIN_FILENO, buf, sizeof(buf))) == -1) {
-				if(errno != EAGAIN && errno != EWOULDBLOCK)
-					goto fini;
-			} else if(r > 0) {
+			if((r = readfd(STDIN_FILENO, (char *)buf, sizeof(buf))) == -1)
+				goto fini;
+			if(r > 0) {
 				buf[r] = '\0';
 				handleinput(buf, r);
+			} else if(r == 0) {
+				ts.tv_sec = tv.tv_sec;
+				ts.tv_nsec = tv.tv_usec * 1000;
+				nanosleep(&ts, NULL);
 			}
 		}
 	}