Moved "generic" fd I/O functions from picocom.c to fdio.[ch]

fdio.c

@@ -0,0 +1,167 @@
+/* vi: set sw=4 ts=4:
+ *
+ * fdio.c
+ *
+ * Functions for doing I/O on file descriptors.
+ *
+ * by Nick Patavalis (npat@efault.net)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+ * USA 
+ */
+
+#include <stdlib.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdarg.h>
+
+/**********************************************************************/
+
+ssize_t
+writen_ni(int fd, const void *buff, size_t n)
+{
+    size_t nl; 
+    ssize_t nw;
+    const char *p;
+
+    p = buff;
+    nl = n;
+    while (nl > 0) {
+        do {
+            nw = write(fd, p, nl);
+        } while ( nw < 0 && errno == EINTR );
+        if ( nw <= 0 ) break;
+        nl -= nw;
+        p += nw;
+    }
+    
+    return n - nl;
+}
+
+int
+fd_printf (int fd, const char *format, ...)
+{
+    char buf[256];
+    va_list args;
+    int len;
+    
+    va_start(args, format);
+    len = vsnprintf(buf, sizeof(buf), format, args);
+    buf[sizeof(buf) - 1] = '\0';
+    va_end(args);
+    
+    return writen_ni(fd, buf, len);
+}
+
+/**********************************************************************/
+
+#ifndef LINENOISE
+
+static int 
+cput(int fd, char c) 
+{ 
+    return write(fd, &c, 1); 
+}
+
+static int 
+cdel (int fd)
+{
+    const char del[] = "\b \b";
+    return write(fd, del, sizeof(del) - 1);
+}
+
+static int 
+xput (int fd, unsigned char c)
+{
+    const char hex[] = "0123456789abcdef"; 
+    char b[4];
+
+    b[0] = '\\'; b[1] = 'x'; b[2] = hex[c >> 4]; b[3] = hex[c & 0x0f];
+    return write(fd, b, sizeof(b) - 1);
+}
+
+static int 
+xdel (int fd)
+{
+    const char del[] = "\b\b\b\b    \b\b\b\b";
+    return write(fd, del, sizeof(del) - 1);
+}
+
+int
+fd_readline (int fdi, int fdo, char *b, int bsz)
+{
+    int r;
+    unsigned char c;
+    unsigned char *bp, *bpe;
+    
+    bp = (unsigned char *)b;
+    bpe = (unsigned char *)b + bsz - 1;
+
+    while (1) {
+        r = read(fdi, &c, 1);
+        if ( r <= 0 ) { r = -1; goto out; }
+
+        switch (c) {
+        case '\b':
+        case '\x7f':
+            if ( bp > (unsigned char *)b ) { 
+                bp--;
+                if ( isprint(*bp) ) 
+                    cdel(fdo);
+                else 
+                    xdel(fdo);
+            } else {
+                cput(fdo, '\x07');
+            }
+            break;
+        case '\x03': /* CTRL-c */
+            r = -1;
+            errno = EINTR;
+            goto out;
+        case '\r':
+            *bp = '\0';
+            r = bp - (unsigned char *)b; 
+            goto out;
+        default:
+            if ( bp < bpe ) { 
+                *bp++ = c;
+                if ( isprint(c) ) 
+                    cput(fdo, c); 
+                else 
+                    xput(fdo, c);
+            } else { 
+                cput(fdo, '\x07'); 
+            }
+            break;
+        }
+    }
+
+out:
+    return r;
+}
+
+#endif /* of LINENOISE */
+
+/**********************************************************************/
+
+/*
+ * Local Variables:
+ * mode:c
+ * tab-width: 4
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */