Merge branch 'busybox' into merge

8 files changed, 166 insertions, 45 deletions

diff --git a/coreutils/Kbuild.src b/coreutils/Kbuild.src
index b715b9c47..ec4ef7df2 100644
--- a/coreutils/Kbuild.src
+++ b/coreutils/Kbuild.src
@@ -35,7 +35,6 @@ lib-$(CONFIG_EXPAND)    += expand.o
 lib-$(CONFIG_FALSE)     += false.o
 lib-$(CONFIG_FOLD)      += fold.o
 lib-$(CONFIG_FSYNC)     += fsync.o
-lib-$(CONFIG_HEAD)      += head.o
 lib-$(CONFIG_INSTALL)   += install.o
 #lib-$(CONFIG_LENGTH)    += length.o
 lib-$(CONFIG_LN)        += ln.o
@@ -71,7 +70,6 @@ lib-$(CONFIG_STTY)      += stty.o
 lib-$(CONFIG_SUM)       += sum.o
 lib-$(CONFIG_SYNC)      += sync.o
 lib-$(CONFIG_TAC)       += tac.o
-lib-$(CONFIG_TAIL)      += tail.o
 lib-$(CONFIG_TEE)       += tee.o
 lib-$(CONFIG_TRUE)      += true.o
 lib-$(CONFIG_TTY)       += tty.o
diff --git a/coreutils/head.c b/coreutils/head.c
index ec4512765..291e1ce37 100644
--- a/coreutils/head.c
+++ b/coreutils/head.c
@@ -11,6 +11,9 @@
 /* BB_AUDIT GNU compatible -c, -q, and -v options in 'fancy' configuration. */
 /* http://www.opengroup.org/onlinepubs/007904975/utilities/head.html */
 
+//kbuild:lib-$(CONFIG_HEAD) += head.o
+//kbuild:lib-$(CONFIG_HEAD) += head_tail.o
+
 //usage:#define head_trivial_usage
 //usage:       "[OPTIONS] [FILE]..."
 //usage:#define head_full_usage "\n\n"
@@ -18,7 +21,8 @@
 //usage:       "With more than one FILE, precede each with a filename header.\n"
 //usage:     "\n        -n N[kbm]       Print first N lines"
 //usage:        IF_FEATURE_FANCY_HEAD(
-//usage:     "\n        -c N[kbm]       Print first N bytes"
+//usage:     "\n        -n -N[kbm]      Print all except N last lines"
+//usage:     "\n        -c [-]N[kbm]    Print first N bytes"
 //usage:     "\n        -q              Never print headers"
 //usage:     "\n        -v              Always print headers"
 //usage:        )
@@ -31,9 +35,114 @@
 //usage:       "daemon:x:1:1:daemon:/usr/sbin:/bin/sh\n"
 
 #include "libbb.h"
+#include "head_tail.h"
 
 /* This is a NOEXEC applet. Be very careful! */
 
+#if !ENABLE_FEATURE_FANCY_HEAD
+# define print_first_N(fp,count,bytes) print_first_N(fp,count)
+#endif
+static void
+print_first_N(FILE *fp, unsigned long count, bool count_bytes)
+{
+#if !ENABLE_FEATURE_FANCY_HEAD
+        const int count_bytes = 0;
+#endif
+        while (count) {
+                int c = getc(fp);
+                if (c == EOF)
+                        break;
+                if (count_bytes || (c == '\n'))
+                        --count;
+                putchar(c);
+        }
+}
+
+#if ENABLE_FEATURE_FANCY_HEAD
+static void
+print_except_N_last_bytes(FILE *fp, unsigned count)
+{
+        unsigned char *circle = xmalloc(++count);
+        unsigned head = 0;
+        for(;;) {
+                int c;
+                c = getc(fp);
+                if (c == EOF)
+                        goto ret;
+                circle[head++] = c;
+                if (head == count)
+                        break;
+        }
+        for (;;) {
+                int c;
+                if (head == count)
+                        head = 0;
+                putchar(circle[head]);
+                c = getc(fp);
+                if (c == EOF)
+                        goto ret;
+                circle[head] = c;
+                head++;
+        }
+ ret:
+        free(circle);
+}
+
+static void
+print_except_N_last_lines(FILE *fp, unsigned count)
+{
+        char **circle = xzalloc((++count) * sizeof(circle[0]));
+        unsigned head = 0;
+        for(;;) {
+                char *c;
+                c = xmalloc_fgets(fp);
+                if (!c)
+                        goto ret;
+                circle[head++] = c;
+                if (head == count)
+                        break;
+        }
+        for (;;) {
+                char *c;
+                if (head == count)
+                        head = 0;
+                fputs(circle[head], stdout);
+                c = xmalloc_fgets(fp);
+                if (!c)
+                        goto ret;
+                free(circle[head]);
+                circle[head++] = c;
+        }
+ ret:
+        head = 0;
+        for(;;) {
+                free(circle[head++]);
+                if (head == count)
+                        break;
+        }
+        free(circle);
+}
+#else
+/* Must never be called */
+void print_except_N_last_bytes(FILE *fp, unsigned count);
+void print_except_N_last_lines(FILE *fp, unsigned count);
+#endif
+
+#if !ENABLE_FEATURE_FANCY_HEAD
+# define eat_num(negative_N,p) eat_num(p)
+#endif
+static unsigned long
+eat_num(bool *negative_N, const char *p)
+{
+#if ENABLE_FEATURE_FANCY_HEAD
+        if (*p == '-') {
+                *negative_N = 1;
+                p++;
+        }
+#endif
+        return xatoul_sfx(p, head_tail_suffixes);
+}
+
 static const char head_opts[] ALIGN1 =
         "n:"
 #if ENABLE_FEATURE_FANCY_HEAD
@@ -41,29 +150,25 @@ static const char head_opts[] ALIGN1 =
 #endif
         ;
 
-static const struct suffix_mult head_suffixes[] = {
-        { "b", 512 },
-        { "k", 1024 },
-        { "m", 1024*1024 },
-        { "", 0 }
-};
-
 #define header_fmt_str "\n==> %s <==\n"
 
 int head_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int head_main(int argc, char **argv)
 {
         unsigned long count = 10;
-        unsigned long i;
 #if ENABLE_FEATURE_FANCY_HEAD
-        int count_bytes = 0;
         int header_threshhold = 1;
+        bool count_bytes = 0;
+        bool negative_N = 0;
+#else
+# define header_threshhold 1
+# define count_bytes       0
+# define negative_N        0
 #endif
         FILE *fp;
         const char *fmt;
         char *p;
         int opt;
-        int c;
         int retval = EXIT_SUCCESS;
 
 #if ENABLE_INCLUDE_SUSv2 || ENABLE_FEATURE_FANCY_HEAD
@@ -73,7 +178,7 @@ int head_main(int argc, char **argv)
         ) {
                 --argc;
                 ++argv;
-                p = (*argv) + 1;
+                p = argv[0] + 1;
                 goto GET_COUNT;
         }
 #endif
@@ -97,7 +202,7 @@ int head_main(int argc, char **argv)
 #if ENABLE_INCLUDE_SUSv2 || ENABLE_FEATURE_FANCY_HEAD
  GET_COUNT:
 #endif
-                        count = xatoul_sfx(p, head_suffixes);
+                        count = eat_num(&negative_N, p);
                         break;
                 default:
                         bb_show_usage();
@@ -110,19 +215,17 @@ int head_main(int argc, char **argv)
                 *--argv = (char*)"-";
 
         fmt = header_fmt_str + 1;
-#if ENABLE_FEATURE_FANCY_HEAD
         if (argc <= header_threshhold) {
+#if ENABLE_FEATURE_FANCY_HEAD
                 header_threshhold = 0;
-        }
 #else
-        if (argc <= 1) {
                 fmt += 11; /* "" */
-        }
-        /* Now define some things here to avoid #ifdefs in the code below.
-         * These should optimize out of the if conditions below. */
-#define header_threshhold   1
-#define count_bytes         0
 #endif
+        }
+        if (negative_N) {
+                if (count >= INT_MAX / sizeof(char*))
+                        bb_error_msg("count is too big: %lu", count);
+        }
 
         do {
                 fp = fopen_or_warn_stdin(*argv);
@@ -133,18 +236,20 @@ int head_main(int argc, char **argv)
                         if (header_threshhold) {
                                 printf(fmt, *argv);
                         }
-                        i = count;
-                        while (i && ((c = getc(fp)) != EOF)) {
-                                if (count_bytes || (c == '\n')) {
-                                        --i;
+                        if (negative_N) {
+                                if (count_bytes) {
+                                        print_except_N_last_bytes(fp, count);
+                                } else {
+                                        print_except_N_last_lines(fp, count);
                                 }
-                                putchar(c);
+                        } else {
+                                print_first_N(fp, count, count_bytes);
                         }
+                        die_if_ferror_stdout();
                         if (fclose_if_not_stdin(fp)) {
                                 bb_simple_perror_msg(*argv);
                                 retval = EXIT_FAILURE;
                         }
-                        die_if_ferror_stdout();
                 } else {
                         retval = EXIT_FAILURE;
                 }
diff --git a/coreutils/head_tail.c b/coreutils/head_tail.c
new file mode 100644
index 000000000..1658c0d1b
--- /dev/null
+++ b/coreutils/head_tail.c
@@ -0,0 +1,14 @@
+/*
+ * Copyright (C) 2013 Denys Vlasenko
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
+ */
+#include "libbb.h"
+#include "head_tail.h"
+
+const struct suffix_mult head_tail_suffixes[] = {
+        { "b", 512 },
+        { "k", 1024 },
+        { "m", 1024*1024 },
+        { "", 0 }
+};
diff --git a/coreutils/head_tail.h b/coreutils/head_tail.h
new file mode 100644
index 000000000..df19e41e0
--- /dev/null
+++ b/coreutils/head_tail.h
@@ -0,0 +1,6 @@
+/*
+ * Copyright (C) 2013 Denys Vlasenko
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
+ */
+extern const struct suffix_mult head_tail_suffixes[];
diff --git a/coreutils/hostid.c b/coreutils/hostid.c
index 5c1a4e086..e5b1f5188 100644
--- a/coreutils/hostid.c
+++ b/coreutils/hostid.c
@@ -36,7 +36,8 @@ int hostid_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
                 bb_show_usage();
         }
 
-        printf("%08lx\n", gethostid());
+        /* POSIX says gethostid returns a "32-bit identifier" */
+        printf("%08x\n", (unsigned)(uint32_t)gethostid());
 
         return fflush_all();
 }
diff --git a/coreutils/id.c b/coreutils/id.c
index 1f20b755e..1f3e1c4c2 100644
--- a/coreutils/id.c
+++ b/coreutils/id.c
@@ -64,12 +64,10 @@
 /* This is a NOEXEC applet. Be very careful! */
 
 #if !ENABLE_USE_BB_PWD_GRP
-#if defined(__UCLIBC_MAJOR__) && (__UCLIBC_MAJOR__ == 0)
-#if (__UCLIBC_MINOR__ < 9) || (__UCLIBC_MINOR__ == 9 &&  __UCLIBC_SUBLEVEL__ < 30)
+#if defined(__UCLIBC__) && UCLIBC_VERSION < KERNEL_VERSION(0, 9, 30)
 #error "Sorry, you need at least uClibc version 0.9.30 for id applet to build"
 #endif
 #endif
-#endif
 
 enum {
         PRINT_REAL      = (1 << 0),
diff --git a/coreutils/readlink.c b/coreutils/readlink.c
index f7ad791ec..d73ef4ddb 100644
--- a/coreutils/readlink.c
+++ b/coreutils/readlink.c
@@ -39,7 +39,10 @@
  *   -q, --quiet, -s, --silent     suppress most error messages
  *   -v, --verbose                 report error messages
  *
- * bbox supports: -f -n -v (fully), -q -s (accepts but ignores)
+ * bbox supports: -f (partially) -n -v (fully), -q -s (accepts but ignores)
+ * Note: we export the -f flag, but our -f behaves like coreutils' -e.
+ * Unfortunately, there isn't a C lib function we can leverage to get this
+ * behavior which means we'd have to implement the full stack ourselves :(.
  */
 
 int readlink_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
diff --git a/coreutils/tail.c b/coreutils/tail.c
index b376ec863..19fd8f695 100644
--- a/coreutils/tail.c
+++ b/coreutils/tail.c
@@ -24,6 +24,9 @@
  * 7) lseek attempted when count==0 even if arg was +0 (from top)
  */
 
+//kbuild:lib-$(CONFIG_TAIL) += tail.o
+//kbuild:lib-$(CONFIG_TAIL) += head_tail.o
+
 //usage:#define tail_trivial_usage
 //usage:       "[OPTIONS] [FILE]..."
 //usage:#define tail_full_usage "\n\n"
@@ -34,14 +37,13 @@
 //usage:     "\n        -s SECONDS      Wait SECONDS between reads with -f"
 //usage:        )
 //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        -c N[kbm]       Print last N bytes"
+//usage:     "\n        -c [+]N[kbm]    Print last N bytes"
 //usage:     "\n        -q              Never print headers"
 //usage:     "\n        -v              Always print headers"
 //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:
 //usage:#define tail_example_usage
@@ -49,13 +51,7 @@
 //usage:       "nameserver 10.0.0.1\n"
 
 #include "libbb.h"
-
-static const struct suffix_mult tail_suffixes[] = {
-        { "b", 512 },
-        { "k", 1024 },
-        { "m", 1024*1024 },
-        { "", 0 }
-};
+#include "head_tail.h"
 
 struct globals {
         bool from_top;
@@ -102,7 +98,7 @@ static unsigned eat_num(const char *p)
                 p++;
                 G.from_top = 1;
         }
-        return xatou_sfx(p, tail_suffixes);
+        return xatou_sfx(p, head_tail_suffixes);
 }
 
 int tail_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;