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Diffstat (limited to 'coreutils/expand.c')
| -rw-r--r-- | coreutils/expand.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/coreutils/expand.c b/coreutils/expand.c new file mode 100644 index 0000000..ee51c03 --- /dev/null +++ b/coreutils/expand.c @@ -0,0 +1,200 @@ +/* expand - convert tabs to spaces + * unexpand - convert spaces to tabs + * + * Copyright (C) 89, 91, 1995-2006 Free Software Foundation, Inc. + * + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. + * + * David MacKenzie <djm@gnu.ai.mit.edu> + * + * Options for expand: + * -t num --tabs=NUM Convert tabs to num spaces (default 8 spaces). + * -i --initial Only convert initial tabs on each line to spaces. + * + * Options for unexpand: + * -a --all Convert all blanks, instead of just initial blanks. + * -f --first-only Convert only leading sequences of blanks (default). + * -t num --tabs=NUM Have tabs num characters apart instead of 8. + * + * Busybox version (C) 2007 by Tito Ragusa <farmatito@tiscali.it> + * + * Caveat: this versions of expand and unexpand don't accept tab lists. + */ + +#include "libbb.h" + +enum { + OPT_INITIAL = 1 << 0, + OPT_TABS = 1 << 1, + OPT_ALL = 1 << 2, +}; + +static void xputchar(char c) +{ + if (putchar(c) < 0) + bb_error_msg_and_die(bb_msg_write_error); +} + +#if ENABLE_EXPAND +static void expand(FILE *file, unsigned tab_size, unsigned opt) +{ + char *line; + char *ptr; + int convert; + unsigned pos; + + /* Increment tab_size by 1 locally.*/ + tab_size++; + + while ((line = xmalloc_fgets(file)) != NULL) { + convert = 1; + pos = 0; + ptr = line; + while (*line) { + pos++; + if (*line == '\t' && convert) { + for (; pos < tab_size; pos++) { + xputchar(' '); + } + } else { + if ((opt & OPT_INITIAL) && !isblank(*line)) { + convert = 0; + } + xputchar(*line); + } + if (pos == tab_size) { + pos = 0; + } + line++; + } + free(ptr); + } +} +#endif + +#if ENABLE_UNEXPAND +static void unexpand(FILE *file, unsigned int tab_size, unsigned opt) +{ + char *line; + char *ptr; + int convert; + int pos; + int i = 0; + unsigned column = 0; + + while ((line = xmalloc_fgets(file)) != NULL) { + convert = 1; + pos = 0; + ptr = line; + while (*line) { + while ((*line == ' ' || *line == '\t') && convert) { + pos += (*line == ' ') ? 1 : tab_size; + line++; + column++; + if ((opt & OPT_ALL) && column == tab_size) { + column = 0; + goto put_tab; + } + } + if (pos) { + i = pos / tab_size; + if (i) { + for (; i > 0; i--) { + put_tab: + xputchar('\t'); + } + } else { + for (i = pos % tab_size; i > 0; i--) { + xputchar(' '); + } + } + pos = 0; + } else { + if (opt & OPT_INITIAL) { + convert = 0; + } + if (opt & OPT_ALL) { + column++; + } + xputchar(*line); + line++; + } + } + free(ptr); + } +} +#endif + +int expand_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int expand_main(int argc UNUSED_PARAM, char **argv) +{ + /* Default 8 spaces for 1 tab */ + const char *opt_t = "8"; + FILE *file; + unsigned tab_size; + unsigned opt; + int exit_status = EXIT_SUCCESS; + +#if ENABLE_FEATURE_EXPAND_LONG_OPTIONS + static const char expand_longopts[] ALIGN1 = + /* name, has_arg, val */ + "initial\0" No_argument "i" + "tabs\0" Required_argument "t" + ; +#endif +#if ENABLE_FEATURE_UNEXPAND_LONG_OPTIONS + static const char unexpand_longopts[] ALIGN1 = + /* name, has_arg, val */ + "first-only\0" No_argument "i" + "tabs\0" Required_argument "t" + "all\0" No_argument "a" + ; +#endif + + if (ENABLE_EXPAND && (!ENABLE_UNEXPAND || applet_name[0] == 'e')) { + USE_FEATURE_EXPAND_LONG_OPTIONS(applet_long_options = expand_longopts); + opt = getopt32(argv, "it:", &opt_t); + } else { + USE_FEATURE_UNEXPAND_LONG_OPTIONS(applet_long_options = unexpand_longopts); + /* -t NUM sets also -a */ + opt_complementary = "ta"; + opt = getopt32(argv, "ft:a", &opt_t); + /* -f --first-only is the default */ + if (!(opt & OPT_ALL)) opt |= OPT_INITIAL; + } + tab_size = xatou_range(opt_t, 1, UINT_MAX); + + argv += optind; + + if (!*argv) { + *--argv = (char*)bb_msg_standard_input; + } + do { + file = fopen_or_warn_stdin(*argv); + if (!file) { + exit_status = EXIT_FAILURE; + continue; + } + + if (ENABLE_EXPAND && (!ENABLE_UNEXPAND || applet_name[0] == 'e')) + USE_EXPAND(expand(file, tab_size, opt)); + else + USE_UNEXPAND(unexpand(file, tab_size, opt)); + + /* Check and close the file */ + if (fclose_if_not_stdin(file)) { + bb_simple_perror_msg(*argv); + exit_status = EXIT_FAILURE; + } + /* If stdin also clear EOF */ + if (file == stdin) + clearerr(file); + } while (*++argv); + + /* Now close stdin also */ + /* (if we didn't read from it, it's a no-op) */ + if (fclose(stdin)) + bb_perror_msg_and_die(bb_msg_standard_input); + + fflush_stdout_and_exit(exit_status); +} |