Fix various compile warnings

[splice.git] / vmsplice.c

diff --git a/vmsplice.c b/vmsplice.c
index 7a037b1b4862ef612d29811685c27765f5ba899a..2cfe6b29b1e544b609aec6b4d27a34320043fa7e 100644 (file)
--- a/vmsplice.c
+++ b/vmsplice.c
@@ -8,35 +8,35 @@
 #include <limits.h>
 #include <string.h>
 #include <getopt.h>
+#include <fcntl.h>
 #include <sys/poll.h>
-#include <sys/stat.h>
 #include <sys/types.h>
 
 #include "splice.h"
 
-#define ALIGN_BUF
-
-#ifdef ALIGN_BUF
-#define ALIGN_MASK     (65535) /* 64k-1, should just be PAGE_SIZE - 1 */
-#define ALIGN(buf)     (void *) (((unsigned long) (buf) + ALIGN_MASK) & ~ALIGN_MASK)
-#else
-#define ALIGN_MASK     (0)
-#define ALIGN(buf)     (buf)
-#endif
+#define ALIGN(buf)     (void *) (((unsigned long) (buf) + align_mask) & ~align_mask)
 
 static int do_clear;
+static int align_mask = 65535;
+static int force_unalign;
+static int splice_flags;
 
-int do_vmsplice(int fd, void *buffer, int len)
+int do_vmsplice(int fd, void *b1, void *b2, int len)
 {
        struct pollfd pfd = { .fd = fd, .events = POLLOUT, };
-       int written;
+       struct iovec iov[] = {
+               {
+                       .iov_base = b1,
+                       .iov_len = len / 2,
+               },
+               {
+                       .iov_base = b2,
+                       .iov_len = len / 2,
+               },
+       };
+       int written, idx = 0;
 
        while (len) {
-               struct iovec iov = {
-                       .iov_base = buffer,
-                       .iov_len = min(SPLICE_SIZE, len),
-               };
-
                /*
                 * in a real app you'd be more clever with poll of course,
                 * here we are basically just blocking on output room and
@@ -45,13 +45,22 @@ int do_vmsplice(int fd, void *buffer, int len)
                if (poll(&pfd, 1, -1) < 0)
                        return error("poll");
 
-               written = vmsplice(fd, &iov, 1, 0);
+               written = svmsplice(fd, &iov[idx], 2 - idx, splice_flags);
 
                if (written <= 0)
                        return error("vmsplice");
 
                len -= written;
-               buffer += written;
+               if ((size_t) written >= iov[idx].iov_len) {
+                       int extra = written - iov[idx].iov_len;
+
+                       idx++;
+                       iov[idx].iov_len -= extra;
+                       iov[idx].iov_base += extra;
+               } else {
+                       iov[idx].iov_len -= written;
+                       iov[idx].iov_base += written;
+               }
        }
 
        return 0;
@@ -59,7 +68,7 @@ int do_vmsplice(int fd, void *buffer, int len)
 
 static int usage(char *name)
 {
-       fprintf(stderr, "%s: [-c]\n", name);
+       fprintf(stderr, "%s: [-c(lear)] [-u(nalign)] [-g(ift)]| ...\n", name);
        return 1;
 }
 
@@ -67,12 +76,20 @@ static int parse_options(int argc, char *argv[])
 {
        int c, index = 1;
 
-       while ((c = getopt(argc, argv, "c")) != -1) {
+       while ((c = getopt(argc, argv, "cug")) != -1) {
                switch (c) {
                case 'c':
                        do_clear = 1;
                        index++;
                        break;
+               case 'u':
+                       force_unalign = 1;
+                       index++;
+                       break;
+               case 'g':
+                       splice_flags = SPLICE_F_GIFT;
+                       index++;
+                       break;
                default:
                        return -1;
                }
@@ -83,29 +100,32 @@ static int parse_options(int argc, char *argv[])
 
 int main(int argc, char *argv[])
 {
-       unsigned char *buffer;
-       struct stat sb;
-       int i;
+       unsigned char *b1, *b2;
 
        if (parse_options(argc, argv) < 0)
                return usage(argv[0]);
 
-       if (fstat(STDOUT_FILENO, &sb) < 0)
-               return error("stat");
-       if (!S_ISFIFO(sb.st_mode)) {
-               fprintf(stderr, "stdout must be a pipe\n");
-               return 1;
+       if (check_output_pipe())
+               return usage(argv[0]);
+
+       b1 = ALIGN(malloc(SPLICE_SIZE + align_mask));
+       b2 = ALIGN(malloc(SPLICE_SIZE + align_mask));
+
+       if (force_unalign) {
+               b1 += 1024;
+               b2 += 1024;
        }
 
-       buffer = ALIGN(malloc(2 * SPLICE_SIZE + ALIGN_MASK));
-       for (i = 0; i < 2 * SPLICE_SIZE; i++)
-               buffer[i] = (i & 0xff);
+       memset(b1, 0xaa, SPLICE_SIZE);
+       memset(b2, 0xbb, SPLICE_SIZE);
 
        do {
+               int half = SPLICE_SIZE / 2;
+
                /*
                 * vmsplice the first half of the buffer into the pipe
                 */
-               if (do_vmsplice(STDOUT_FILENO, buffer, SPLICE_SIZE))
+               if (do_vmsplice(STDOUT_FILENO, b1, b2, SPLICE_SIZE))
                        break;
 
                /*
@@ -116,7 +136,7 @@ int main(int argc, char *argv[])
                /*
                 * vmsplice second half
                 */
-               if (do_vmsplice(STDOUT_FILENO, buffer + SPLICE_SIZE, SPLICE_SIZE))
+               if (do_vmsplice(STDOUT_FILENO, b1 + half, b2 + half, SPLICE_SIZE))
                        break;
 
                /*
@@ -129,9 +149,10 @@ int main(int argc, char *argv[])
                 * Test option - clear the first half of the buffer, should
                 * be safe now
                 */
-               if (do_clear)
-                       memset(buffer, 0x00, SPLICE_SIZE);
-                       
+               if (do_clear) {
+                       memset(b1, 0x00, SPLICE_SIZE);
+                       memset(b2, 0x00, SPLICE_SIZE);
+               }
        } while (0);
 
        return 0;