config: more tweaks
[oweals/busybox.git] / coreutils / fold.c
index e45a75b33e183d0cceabc42d6d75c2d884c58c0c..1e26dde0c52f7697e9a884a10f8fa73ee4fd000f 100644 (file)
-/* fold -- wrap each input line to fit in specified width.
-
-   Written by David MacKenzie, djm@gnu.ai.mit.edu.
-   Copyright (C) 91, 1995-2002 Free Software Foundation, Inc.
-
-   Modified for busybox based on coreutils v 5.0
-   Copyright (C) 2003 Glenn McGrath <bug1@iinet.net.au>
-
-   Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
-*/
-
-#include <ctype.h>
-#include <errno.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/types.h>
-#include <unistd.h>
-#include "busybox.h"
-
-/* If nonzero, count bytes, not column positions. */
-static unsigned long flags;
-#define FLAG_COUNT_BYTES       1
-#define FLAG_BREAK_SPACES      2
-#define FLAG_WIDTH                     4
+/* vi: set sw=4 ts=4: */
+/*
+ * fold -- wrap each input line to fit in specified width.
+ *
+ * Written by David MacKenzie, djm@gnu.ai.mit.edu.
+ * Copyright (C) 91, 1995-2002 Free Software Foundation, Inc.
+ *
+ * Modified for busybox based on coreutils v 5.0
+ * Copyright (C) 2003 Glenn McGrath
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+//config:config FOLD
+//config:      bool "fold (4.6 kb)"
+//config:      default y
+//config:      help
+//config:      Wrap text to fit a specific width.
+
+//applet:IF_FOLD(APPLET_NOEXEC(fold, fold, BB_DIR_USR_BIN, BB_SUID_DROP, fold))
+
+//kbuild:lib-$(CONFIG_FOLD) += fold.o
+
+//usage:#define fold_trivial_usage
+//usage:       "[-bs] [-w WIDTH] [FILE]..."
+//usage:#define fold_full_usage "\n\n"
+//usage:       "Wrap input lines in each FILE (or stdin), writing to stdout\n"
+//usage:     "\n       -b      Count bytes rather than columns"
+//usage:     "\n       -s      Break at spaces"
+//usage:     "\n       -w      Use WIDTH columns instead of 80"
+
+#include "libbb.h"
+#include "unicode.h"
+
+/* This is a NOEXEC applet. Be very careful! */
+
+/* Must match getopt32 call */
+#define FLAG_COUNT_BYTES        1
+#define FLAG_BREAK_SPACES       2
+#define FLAG_WIDTH              4
 
 /* Assuming the current column is COLUMN, return the column that
    printing C will move the cursor to.
    The first column is 0. */
-
-static int adjust_column(int column, char c)
+static int adjust_column(unsigned column, char c)
 {
-       if (!(flags & FLAG_COUNT_BYTES)) {
-               if (c == '\b') {
-                       if (column > 0)
-                               column--;
-               } else if (c == '\r')
+       if (option_mask32 & FLAG_COUNT_BYTES)
+               return ++column;
+
+       if (c == '\t')
+               return column + 8 - column % 8;
+
+       if (c == '\b') {
+               if ((int)--column < 0)
                        column = 0;
-               else if (c == '\t')
-                       column = column + 8 - column % 8;
-               else                    /* if (isprint (c)) */
+       }
+       else if (c == '\r')
+               column = 0;
+       else { /* just a printable char */
+               if (unicode_status != UNICODE_ON /* every byte is a new char */
+                || (c & 0xc0) != 0x80 /* it isn't a 2nd+ byte of a Unicode char */
+               ) {
                        column++;
-       } else
-               column++;
+               }
+       }
        return column;
 }
 
-extern int fold_main(int argc, char **argv)
+/* Note that this function can write NULs, unlike fputs etc. */
+static void write2stdout(const void *buf, unsigned size)
 {
-       char *w_opt;
-
-       /* If nonzero, at least one of the files we read was standard input. */
-       int have_read_stdin = 0;
-
-       int width = 80;
-       int i;
-       int errs = 0;
-
-       have_read_stdin = 0;
-
-       /* Turn any numeric options into -w options.  */
-       for (i = 1; i < argc; i++) {
-               char const *a = argv[i];
-
-               if (a[0] == '-') {
-                       if (a[1] == '-' && !a[2])
-                               break;
-                       if (isdigit(a[1])) {
-                               char *s = xmalloc(strlen(a) + 2);
+       fwrite(buf, 1, size, stdout);
+}
 
-                               s[0] = '-';
-                               s[1] = 'w';
-                               strcpy(s + 2, a + 1);
-                               argv[i] = s;
+int fold_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int fold_main(int argc UNUSED_PARAM, char **argv)
+{
+       char *line_out = NULL;
+       const char *w_opt = "80";
+       unsigned width;
+       smallint exitcode = EXIT_SUCCESS;
+
+       init_unicode();
+
+       if (ENABLE_INCLUDE_SUSv2) {
+               /* Turn any numeric options into -w options.  */
+               int i;
+               for (i = 1; argv[i]; i++) {
+                       const char *a = argv[i];
+                       if (*a == '-') {
+                               a++;
+                               if (*a == '-' && !a[1]) /* "--" */
+                                       break;
+                               if (isdigit(*a))
+                                       argv[i] = xasprintf("-w%s", a);
                        }
                }
        }
 
-       flags = bb_getopt_ulflags(argc, argv, "bsw:", &w_opt);
-       if (flags & 4)
-               width = bb_xgetlarg(w_opt, 10, 1, 10000);
+       getopt32(argv, "bsw:", &w_opt);
+       width = xatou_range(w_opt, 1, 10000);
 
        argv += optind;
-       if (!*argv) {
-               *--argv = "-";
-       }
+       if (!*argv)
+               *--argv = (char*)"-";
 
        do {
-               FILE *istream = bb_wfopen_input(*argv);
-               if (istream != NULL) {
-                       int c;
-                       int column = 0;         /* Screen column where next char will go. */
-                       int offset_out = 0;     /* Index in `line_out' for next char. */
-                       static char *line_out = NULL;
-                       static int allocated_out = 0;
-
-                       while ((c = getc(istream)) != EOF) {
-                               if (offset_out + 1 >= allocated_out) {
-                                       allocated_out += 1024;
-                                       line_out = xrealloc(line_out, allocated_out);
-                               }
+               FILE *istream = fopen_or_warn_stdin(*argv);
+               int c;
+               unsigned column = 0;     /* Screen column where next char will go */
+               unsigned offset_out = 0; /* Index in 'line_out' for next char */
+
+               if (istream == NULL) {
+                       exitcode = EXIT_FAILURE;
+                       continue;
+               }
 
-                               if (c == '\n') {
-                                       line_out[offset_out++] = c;
-                                       fwrite(line_out, sizeof(char), (size_t) offset_out, stdout);
-                                       column = offset_out = 0;
-                                       continue;
-                               }
+               while ((c = getc(istream)) != EOF) {
+                       /* We grow line_out in chunks of 0x1000 bytes */
+                       if ((offset_out & 0xfff) == 0) {
+                               line_out = xrealloc(line_out, offset_out + 0x1000);
+                       }
+ rescan:
+                       line_out[offset_out] = c;
+                       if (c == '\n') {
+                               write2stdout(line_out, offset_out + 1);
+                               column = offset_out = 0;
+                               continue;
+                       }
+                       column = adjust_column(column, c);
+                       if (column <= width || offset_out == 0) {
+                               /* offset_out == 0 case happens
+                                * with small width (say, 1) and tabs.
+                                * The very first tab already goes to column 8,
+                                * but we must not wrap it */
+                               offset_out++;
+                               continue;
+                       }
 
-rescan:
-                               column = adjust_column(column, c);
-
-                               if (column > width) {
-                                       /* This character would make the line too long.
-                                         Print the line plus a newline, and make this character
-                                          start the next line. */
-                                       if (flags & FLAG_BREAK_SPACES) {
-                                               /* Look for the last blank. */
-                                               int logical_end;
-
-                                               for (logical_end = offset_out - 1; logical_end >= 0; logical_end--) {
-                                                       if (isblank(line_out[logical_end])) {
-                                                               break;
-                                                       }
-                                               }
-                                               if (logical_end >= 0) {
-                                                       /* Found a blank.  Don't output the part after it. */
-                                                       logical_end++;
-                                                       fwrite(line_out, sizeof(char), (size_t) logical_end, stdout);
-                                                       putchar('\n');
-                                                       /* Move the remainder to the beginning of the next line.
-                                                          The areas being copied here might overlap. */
-                                                       memmove(line_out, line_out + logical_end, offset_out - logical_end);
-                                                       offset_out -= logical_end;
-                                                       for (column = i = 0; i < offset_out; i++) {
-                                                               column = adjust_column(column, line_out[i]);
-                                                       }
-                                                       goto rescan;
-                                               }
-                                       } else {
-                                               if (offset_out == 0) {
-                                                       line_out[offset_out++] = c;
-                                                       continue;
-                                               }
+                       /* This character would make the line too long.
+                        * Print the line plus a newline, and make this character
+                        * start the next line */
+                       if (option_mask32 & FLAG_BREAK_SPACES) {
+                               unsigned i;
+                               unsigned logical_end;
+
+                               /* Look for the last blank. */
+                               for (logical_end = offset_out - 1; (int)logical_end >= 0; logical_end--) {
+                                       if (!isblank(line_out[logical_end]))
+                                               continue;
+
+                                       /* Found a space or tab.
+                                        * Output up to and including it, and start a new line */
+                                       logical_end++;
+                                       /*line_out[logical_end] = '\n'; - NO! this nukes one buffered character */
+                                       write2stdout(line_out, logical_end);
+                                       putchar('\n');
+                                       /* Move the remainder to the beginning of the next line.
+                                        * The areas being copied here might overlap. */
+                                       memmove(line_out, line_out + logical_end, offset_out - logical_end);
+                                       offset_out -= logical_end;
+                                       for (column = i = 0; i < offset_out; i++) {
+                                               column = adjust_column(column, line_out[i]);
                                        }
-                                       line_out[offset_out++] = '\n';
-                                       fwrite(line_out, sizeof(char), (size_t) offset_out, stdout);
-                                       column = offset_out = 0;
                                        goto rescan;
                                }
-
-                               line_out[offset_out++] = c;
-                       }
-
-                       if (offset_out) {
-                               fwrite(line_out, sizeof(char), (size_t) offset_out, stdout);
+                               /* No blank found, wrap will split the overlong word */
                        }
+                       /* Output what we accumulated up to now, and start a new line */
+                       line_out[offset_out] = '\n';
+                       write2stdout(line_out, offset_out + 1);
+                       column = offset_out = 0;
+                       goto rescan;
+               } /* while (not EOF) */
+
+               if (offset_out) {
+                       write2stdout(line_out, offset_out);
+               }
 
-                       if (ferror(istream) || bb_fclose_nonstdin(istream)) {
-                               bb_perror_msg("%s", *argv);     /* Avoid multibyte problems. */
-                               errs |= EXIT_FAILURE;
-                       }
-               } else {
-                       errs |= EXIT_FAILURE;
+               if (fclose_if_not_stdin(istream)) {
+                       bb_simple_perror_msg(*argv);
+                       exitcode = EXIT_FAILURE;
                }
        } while (*++argv);
 
-       bb_fflush_stdout_and_exit(errs);
+       fflush_stdout_and_exit(exitcode);
 }