Changeset 3621 in MondoRescue for branches/3.3/mindi-busybox/coreutils/tail.c

Timestamp:

Dec 20, 2016, 4:07:32 PM (7 years ago)

Author:

Bruno Cornec

Message:

New 3?3 banch for incorporation of latest busybox 1.25. Changing minor version to handle potential incompatibilities.

Location:

branches/3.3

Files:

• . (copied) (copied from branches/3.2 )
• mindi-busybox/coreutils/tail.c (modified) (9 diffs)

branches/3.3/mindi-busybox/coreutils/tail.c

@@ -25 +25 @@
  */
 
+//kbuild:lib-$(CONFIG_TAIL) += tail.o
+
 //usage:#define tail_trivial_usage
 //usage:       "[OPTIONS] [FILE]..."
@@ -31 +33 @@
 //usage:       "With more than one FILE, precede each with a filename header.\n"
 //usage:     "\n    -f      Print data as file grows"
+//usage:     "\n    -c [+]N[kbm]    Print last N bytes"
+//usage:     "\n    -n N[kbm]   Print last N lines"
+//usage:     "\n    -n +N[kbm]  Start on Nth line and print the rest"
 //usage:    IF_FEATURE_FANCY_TAIL(
+//usage:     "\n    -q      Never print headers"
 //usage:     "\n    -s SECONDS  Wait SECONDS between reads with -f"
-//usage:    )
-//usage:     "\n    -n N[kbm]   Print last N lines"
-//usage:    IF_FEATURE_FANCY_TAIL(
-//usage:     "\n    -c N[kbm]   Print last N bytes"
-//usage:     "\n    -q      Never print headers"
 //usage:     "\n    -v      Always print headers"
+//usage:     "\n    -F      Same as -f, but keep retrying"
 //usage:     "\n"
 //usage:     "\nN may be suffixed by k (x1024), b (x512), or m (x1024^2)."
-//usage:     "\nIf N starts with a '+', output begins with the Nth item from the start"
-//usage:     "\nof each file, not from the end."
 //usage:    )
 //usage:
@@ -50 +50 @@
 
 #include "libbb.h"
-
-static const struct suffix_mult tail_suffixes[] = {
-    { "b", 512 },
-    { "k", 1024 },
-    { "m", 1024*1024 },
-    { "", 0 }
-};
+#include "common_bufsiz.h"
 
 struct globals {
@@ -62 +56 @@
     bool exitcode;
 } FIX_ALIASING;
-#define G (*(struct globals*)&bb_common_bufsiz1)
-#define INIT_G() do { } while (0)
+#define G (*(struct globals*)bb_common_bufsiz1)
+#define INIT_G() do { setup_common_bufsiz(); } while (0)
 
 static void tail_xprint_header(const char *fmt, const char *filename)
@@ -74 +68 @@
 {
     ssize_t r;
-    off_t current;
-    struct stat sbuf;
-
-    /* /proc files report zero st_size, don't lseek them. */
-    if (fstat(fd, &sbuf) == 0 && sbuf.st_size > 0) {
-        current = lseek(fd, 0, SEEK_CUR);
-        if (sbuf.st_size < current)
-            xlseek(fd, 0, SEEK_SET);
-    }
 
     r = full_read(fd, buf, count);
@@ -103 +88 @@
         G.from_top = 1;
     }
-    return xatou_sfx(p, tail_suffixes);
+    return xatou_sfx(p, bkm_suffixes);
 }
 
@@ -121 +106 @@
     int *fds;
     const char *fmt;
+    int prev_fd;
 
     INIT_G();
@@ -325 +311 @@
         }
     } while (++i < nfiles);
+    prev_fd = fds[i-1];
 
     tailbuf = xrealloc(tailbuf, BUFSIZ);
@@ -368 +355 @@
                 fmt = header_fmt_str;
             }
-            while ((nread = tail_read(fd, tailbuf, BUFSIZ)) > 0) {
-                if (fmt) {
+            for (;;) {
+                /* tail -f keeps following files even if they are truncated */
+                struct stat sbuf;
+                /* /proc files report zero st_size, don't lseek them */
+                if (fstat(fd, &sbuf) == 0 && sbuf.st_size > 0) {
+                    off_t current = lseek(fd, 0, SEEK_CUR);
+                    if (sbuf.st_size < current)
+                        xlseek(fd, 0, SEEK_SET);
+                }
+
+                nread = tail_read(fd, tailbuf, BUFSIZ);
+                if (nread <= 0)
+                    break;
+                if (fmt && (fd != prev_fd)) {
                     tail_xprint_header(fmt, filename);
                     fmt = NULL;
+                    prev_fd = fd;
                 }
                 xwrite(STDOUT_FILENO, tailbuf, nread);