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Diffstat (limited to 'examples/loadables/strftime.c')
-rw-r--r-- | examples/loadables/strftime.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/examples/loadables/strftime.c b/examples/loadables/strftime.c new file mode 100644 index 0000000..92f489e --- /dev/null +++ b/examples/loadables/strftime.c @@ -0,0 +1,105 @@ +/* strftime - loadable builtin interface to strftime(3) */ + +/* See Makefile for compilation details. */ + +#include <config.h> + +#if defined (HAVE_UNISTD_H) +# include <unistd.h> +#endif + +#include "bashtypes.h" +#include "posixtime.h" + +#include <stdio.h> + +#include "builtins.h" +#include "shell.h" +#include "common.h" + +int +strftime_builtin (list) + WORD_LIST *list; +{ + char *format, *tbuf; + size_t tbsize, tsize; + time_t secs; + struct tm *t; + int n; + intmax_t i; + + if (list == 0) + { + builtin_usage (); + return (EX_USAGE); + } + + if (no_options (list)) + return (EX_USAGE); + + format = list->word->word; + if (format == 0 || *format == 0) + { + printf ("\n"); + return (EXECUTION_SUCCESS); + } + + list = list->next; + + if (list && list->word->word) + { + n = legal_number (list->word->word, &i); + if (n == 0 || i < 0 || i != (time_t)i) + { + sh_invalidnum (list->word->word); + return (EXECUTION_FAILURE); + } + else + secs = i; + } + else + secs = NOW; + + t = localtime (&secs); + + tbsize = strlen (format) * 4; + tbuf = 0; + + /* Now try to figure out how big the buffer should really be. strftime(3) + will return the number of bytes placed in the buffer unless it's greater + than MAXSIZE, in which case it returns 0. */ + for (n = 1; n < 4; n++) + { + tbuf = xrealloc (tbuf, tbsize * n); + tsize = strftime (tbuf, tbsize * n, format, t); + if (tsize) + break; + } + + printf ("%s\n", tbuf); + free (tbuf); + + return (EXECUTION_SUCCESS); +} + +/* An array of strings forming the `long' documentation for a builtin xxx, + which is printed by `help xxx'. It must end with a NULL. */ +char *strftime_doc[] = { + "Converts date and time format to a string and displays it on the", + "standard output. If the optional second argument is supplied, it", + "is used as the number of seconds since the epoch to use in the", + "conversion, otherwise the current time is used.", + (char *)NULL +}; + +/* The standard structure describing a builtin command. bash keeps an array + of these structures. The flags must include BUILTIN_ENABLED so the + builtin can be used. */ +struct builtin strftime_struct = { + "strftime", /* builtin name */ + strftime_builtin, /* function implementing the builtin */ + BUILTIN_ENABLED, /* initial flags for builtin */ + strftime_doc, /* array of long documentation strings. */ + "strftime format [seconds]", /* usage synopsis; becomes short_doc */ + 0 /* reserved for internal use */ +}; |