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-rw-r--r--lib/tilde/tilde.c493
1 files changed, 493 insertions, 0 deletions
diff --git a/lib/tilde/tilde.c b/lib/tilde/tilde.c
new file mode 100644
index 0000000..d678a31
--- /dev/null
+++ b/lib/tilde/tilde.c
@@ -0,0 +1,493 @@
+/* tilde.c -- Tilde expansion code (~/foo := $HOME/foo). */
+
+/* Copyright (C) 1988-2020 Free Software Foundation, Inc.
+
+ This file is part of the GNU Readline Library (Readline), a library
+ for reading lines of text with interactive input and history editing.
+
+ Readline is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ Readline is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with Readline. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#if defined (HAVE_CONFIG_H)
+# include <config.h>
+#endif
+
+#if defined (HAVE_UNISTD_H)
+# ifdef _MINIX
+# include <sys/types.h>
+# endif
+# include <unistd.h>
+#endif
+
+#if defined (HAVE_STRING_H)
+# include <string.h>
+#else /* !HAVE_STRING_H */
+# include <strings.h>
+#endif /* !HAVE_STRING_H */
+
+#if defined (HAVE_STDLIB_H)
+# include <stdlib.h>
+#else
+# include "ansi_stdlib.h"
+#endif /* HAVE_STDLIB_H */
+
+#include <sys/types.h>
+#if defined (HAVE_PWD_H)
+#include <pwd.h>
+#endif
+
+#include "tilde.h"
+
+#if defined (TEST) || defined (STATIC_MALLOC)
+static void *xmalloc (), *xrealloc ();
+#else
+# include "xmalloc.h"
+#endif /* TEST || STATIC_MALLOC */
+
+#if !defined (HAVE_GETPW_DECLS)
+# if defined (HAVE_GETPWUID)
+extern struct passwd *getpwuid (uid_t);
+# endif
+# if defined (HAVE_GETPWNAM)
+extern struct passwd *getpwnam (const char *);
+# endif
+#endif /* !HAVE_GETPW_DECLS */
+
+#if !defined (savestring)
+#define savestring(x) strcpy ((char *)xmalloc (1 + strlen (x)), (x))
+#endif /* !savestring */
+
+#if !defined (NULL)
+# if defined (__STDC__)
+# define NULL ((void *) 0)
+# else
+# define NULL 0x0
+# endif /* !__STDC__ */
+#endif /* !NULL */
+
+/* If being compiled as part of bash, these will be satisfied from
+ variables.o. If being compiled as part of readline, they will
+ be satisfied from shell.o. */
+extern char *sh_get_home_dir (void);
+extern char *sh_get_env_value (const char *);
+
+/* The default value of tilde_additional_prefixes. This is set to
+ whitespace preceding a tilde so that simple programs which do not
+ perform any word separation get desired behaviour. */
+static const char *default_prefixes[] =
+ { " ~", "\t~", (const char *)NULL };
+
+/* The default value of tilde_additional_suffixes. This is set to
+ whitespace or newline so that simple programs which do not
+ perform any word separation get desired behaviour. */
+static const char *default_suffixes[] =
+ { " ", "\n", (const char *)NULL };
+
+/* If non-null, this contains the address of a function that the application
+ wants called before trying the standard tilde expansions. The function
+ is called with the text sans tilde, and returns a malloc()'ed string
+ which is the expansion, or a NULL pointer if the expansion fails. */
+tilde_hook_func_t *tilde_expansion_preexpansion_hook = (tilde_hook_func_t *)NULL;
+
+/* If non-null, this contains the address of a function to call if the
+ standard meaning for expanding a tilde fails. The function is called
+ with the text (sans tilde, as in "foo"), and returns a malloc()'ed string
+ which is the expansion, or a NULL pointer if there is no expansion. */
+tilde_hook_func_t *tilde_expansion_failure_hook = (tilde_hook_func_t *)NULL;
+
+/* When non-null, this is a NULL terminated array of strings which
+ are duplicates for a tilde prefix. Bash uses this to expand
+ `=~' and `:~'. */
+char **tilde_additional_prefixes = (char **)default_prefixes;
+
+/* When non-null, this is a NULL terminated array of strings which match
+ the end of a username, instead of just "/". Bash sets this to
+ `:' and `=~'. */
+char **tilde_additional_suffixes = (char **)default_suffixes;
+
+static int tilde_find_prefix (const char *, int *);
+static int tilde_find_suffix (const char *);
+static char *isolate_tilde_prefix (const char *, int *);
+static char *glue_prefix_and_suffix (char *, const char *, int);
+
+/* Find the start of a tilde expansion in STRING, and return the index of
+ the tilde which starts the expansion. Place the length of the text
+ which identified this tilde starter in LEN, excluding the tilde itself. */
+static int
+tilde_find_prefix (const char *string, int *len)
+{
+ register int i, j, string_len;
+ register char **prefixes;
+
+ prefixes = tilde_additional_prefixes;
+
+ string_len = strlen (string);
+ *len = 0;
+
+ if (*string == '\0' || *string == '~')
+ return (0);
+
+ if (prefixes)
+ {
+ for (i = 0; i < string_len; i++)
+ {
+ for (j = 0; prefixes[j]; j++)
+ {
+ if (strncmp (string + i, prefixes[j], strlen (prefixes[j])) == 0)
+ {
+ *len = strlen (prefixes[j]) - 1;
+ return (i + *len);
+ }
+ }
+ }
+ }
+ return (string_len);
+}
+
+/* Find the end of a tilde expansion in STRING, and return the index of
+ the character which ends the tilde definition. */
+static int
+tilde_find_suffix (const char *string)
+{
+ register int i, j, string_len;
+ register char **suffixes;
+
+ suffixes = tilde_additional_suffixes;
+ string_len = strlen (string);
+
+ for (i = 0; i < string_len; i++)
+ {
+#if defined (__MSDOS__)
+ if (string[i] == '/' || string[i] == '\\' /* || !string[i] */)
+#else
+ if (string[i] == '/' /* || !string[i] */)
+#endif
+ break;
+
+ for (j = 0; suffixes && suffixes[j]; j++)
+ {
+ if (strncmp (string + i, suffixes[j], strlen (suffixes[j])) == 0)
+ return (i);
+ }
+ }
+ return (i);
+}
+
+/* Return a new string which is the result of tilde expanding STRING. */
+char *
+tilde_expand (const char *string)
+{
+ char *result;
+ int result_size, result_index;
+
+ result_index = result_size = 0;
+ if (result = strchr (string, '~'))
+ result = (char *)xmalloc (result_size = (strlen (string) + 16));
+ else
+ result = (char *)xmalloc (result_size = (strlen (string) + 1));
+
+ /* Scan through STRING expanding tildes as we come to them. */
+ while (1)
+ {
+ register int start, end;
+ char *tilde_word, *expansion;
+ int len;
+
+ /* Make START point to the tilde which starts the expansion. */
+ start = tilde_find_prefix (string, &len);
+
+ /* Copy the skipped text into the result. */
+ if ((result_index + start + 1) > result_size)
+ result = (char *)xrealloc (result, 1 + (result_size += (start + 20)));
+
+ strncpy (result + result_index, string, start);
+ result_index += start;
+
+ /* Advance STRING to the starting tilde. */
+ string += start;
+
+ /* Make END be the index of one after the last character of the
+ username. */
+ end = tilde_find_suffix (string);
+
+ /* If both START and END are zero, we are all done. */
+ if (!start && !end)
+ break;
+
+ /* Expand the entire tilde word, and copy it into RESULT. */
+ tilde_word = (char *)xmalloc (1 + end);
+ strncpy (tilde_word, string, end);
+ tilde_word[end] = '\0';
+ string += end;
+
+ expansion = tilde_expand_word (tilde_word);
+
+ if (expansion == 0)
+ expansion = tilde_word;
+ else
+ xfree (tilde_word);
+
+ len = strlen (expansion);
+#ifdef __CYGWIN__
+ /* Fix for Cygwin to prevent ~user/xxx from expanding to //xxx when
+ $HOME for `user' is /. On cygwin, // denotes a network drive. */
+ if (len > 1 || *expansion != '/' || *string != '/')
+#endif
+ {
+ if ((result_index + len + 1) > result_size)
+ result = (char *)xrealloc (result, 1 + (result_size += (len + 20)));
+
+ strcpy (result + result_index, expansion);
+ result_index += len;
+ }
+ xfree (expansion);
+ }
+
+ result[result_index] = '\0';
+
+ return (result);
+}
+
+/* Take FNAME and return the tilde prefix we want expanded. If LENP is
+ non-null, the index of the end of the prefix into FNAME is returned in
+ the location it points to. */
+static char *
+isolate_tilde_prefix (const char *fname, int *lenp)
+{
+ char *ret;
+ int i;
+
+ ret = (char *)xmalloc (strlen (fname));
+#if defined (__MSDOS__)
+ for (i = 1; fname[i] && fname[i] != '/' && fname[i] != '\\'; i++)
+#else
+ for (i = 1; fname[i] && fname[i] != '/'; i++)
+#endif
+ ret[i - 1] = fname[i];
+ ret[i - 1] = '\0';
+ if (lenp)
+ *lenp = i;
+ return ret;
+}
+
+#if 0
+/* Public function to scan a string (FNAME) beginning with a tilde and find
+ the portion of the string that should be passed to the tilde expansion
+ function. Right now, it just calls tilde_find_suffix and allocates new
+ memory, but it can be expanded to do different things later. */
+char *
+tilde_find_word (const char *fname, int flags, int *lenp)
+{
+ int x;
+ char *r;
+
+ x = tilde_find_suffix (fname);
+ if (x == 0)
+ {
+ r = savestring (fname);
+ if (lenp)
+ *lenp = 0;
+ }
+ else
+ {
+ r = (char *)xmalloc (1 + x);
+ strncpy (r, fname, x);
+ r[x] = '\0';
+ if (lenp)
+ *lenp = x;
+ }
+
+ return r;
+}
+#endif
+
+/* Return a string that is PREFIX concatenated with SUFFIX starting at
+ SUFFIND. */
+static char *
+glue_prefix_and_suffix (char *prefix, const char *suffix, int suffind)
+{
+ char *ret;
+ int plen, slen;
+
+ plen = (prefix && *prefix) ? strlen (prefix) : 0;
+ slen = strlen (suffix + suffind);
+ ret = (char *)xmalloc (plen + slen + 1);
+ if (plen)
+ strcpy (ret, prefix);
+ strcpy (ret + plen, suffix + suffind);
+ return ret;
+}
+
+/* Do the work of tilde expansion on FILENAME. FILENAME starts with a
+ tilde. If there is no expansion, call tilde_expansion_failure_hook.
+ This always returns a newly-allocated string, never static storage. */
+char *
+tilde_expand_word (const char *filename)
+{
+ char *dirname, *expansion, *username;
+ int user_len;
+ struct passwd *user_entry;
+
+ if (filename == 0)
+ return ((char *)NULL);
+
+ if (*filename != '~')
+ return (savestring (filename));
+
+ /* A leading `~/' or a bare `~' is *always* translated to the value of
+ $HOME or the home directory of the current user, regardless of any
+ preexpansion hook. */
+ if (filename[1] == '\0' || filename[1] == '/')
+ {
+ /* Prefix $HOME to the rest of the string. */
+ expansion = sh_get_env_value ("HOME");
+#if defined (_WIN32)
+ if (expansion == 0)
+ expansion = sh_get_env_value ("APPDATA");
+#endif
+
+ /* If there is no HOME variable, look up the directory in
+ the password database. */
+ if (expansion == 0)
+ expansion = sh_get_home_dir ();
+
+ return (glue_prefix_and_suffix (expansion, filename, 1));
+ }
+
+ username = isolate_tilde_prefix (filename, &user_len);
+
+ if (tilde_expansion_preexpansion_hook)
+ {
+ expansion = (*tilde_expansion_preexpansion_hook) (username);
+ if (expansion)
+ {
+ dirname = glue_prefix_and_suffix (expansion, filename, user_len);
+ xfree (username);
+ xfree (expansion);
+ return (dirname);
+ }
+ }
+
+ /* No preexpansion hook, or the preexpansion hook failed. Look in the
+ password database. */
+ dirname = (char *)NULL;
+#if defined (HAVE_GETPWNAM)
+ user_entry = getpwnam (username);
+#else
+ user_entry = 0;
+#endif
+ if (user_entry == 0)
+ {
+ /* If the calling program has a special syntax for expanding tildes,
+ and we couldn't find a standard expansion, then let them try. */
+ if (tilde_expansion_failure_hook)
+ {
+ expansion = (*tilde_expansion_failure_hook) (username);
+ if (expansion)
+ {
+ dirname = glue_prefix_and_suffix (expansion, filename, user_len);
+ xfree (expansion);
+ }
+ }
+ /* If we don't have a failure hook, or if the failure hook did not
+ expand the tilde, return a copy of what we were passed. */
+ if (dirname == 0)
+ dirname = savestring (filename);
+ }
+#if defined (HAVE_GETPWENT)
+ else
+ dirname = glue_prefix_and_suffix (user_entry->pw_dir, filename, user_len);
+#endif
+
+ xfree (username);
+#if defined (HAVE_GETPWENT)
+ endpwent ();
+#endif
+ return (dirname);
+}
+
+
+#if defined (TEST)
+#undef NULL
+#include <stdio.h>
+
+main (int argc, char **argv)
+{
+ char *result, line[512];
+ int done = 0;
+
+ while (!done)
+ {
+ printf ("~expand: ");
+ fflush (stdout);
+
+ if (!gets (line))
+ strcpy (line, "done");
+
+ if ((strcmp (line, "done") == 0) ||
+ (strcmp (line, "quit") == 0) ||
+ (strcmp (line, "exit") == 0))
+ {
+ done = 1;
+ break;
+ }
+
+ result = tilde_expand (line);
+ printf (" --> %s\n", result);
+ free (result);
+ }
+ exit (0);
+}
+
+static void memory_error_and_abort (void);
+
+static void *
+xmalloc (size_t bytes)
+{
+ void *temp = (char *)malloc (bytes);
+
+ if (!temp)
+ memory_error_and_abort ();
+ return (temp);
+}
+
+static void *
+xrealloc (void *pointer, int bytes)
+{
+ void *temp;
+
+ if (!pointer)
+ temp = malloc (bytes);
+ else
+ temp = realloc (pointer, bytes);
+
+ if (!temp)
+ memory_error_and_abort ();
+
+ return (temp);
+}
+
+static void
+memory_error_and_abort (void)
+{
+ fprintf (stderr, "readline: out of virtual memory\n");
+ abort ();
+}
+
+/*
+ * Local variables:
+ * compile-command: "gcc -g -DTEST -o tilde tilde.c"
+ * end:
+ */
+#endif /* TEST */
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