diff options
Diffstat (limited to 'protocols/Sametime/src/glib/gshell.c')
| -rw-r--r-- | protocols/Sametime/src/glib/gshell.c | 691 |
1 files changed, 691 insertions, 0 deletions
diff --git a/protocols/Sametime/src/glib/gshell.c b/protocols/Sametime/src/glib/gshell.c new file mode 100644 index 0000000000..1461f29ba2 --- /dev/null +++ b/protocols/Sametime/src/glib/gshell.c @@ -0,0 +1,691 @@ +/* gshell.c - Shell-related utilities + * + * Copyright 2000 Red Hat, Inc. + * g_execvpe implementation based on GNU libc execvp: + * Copyright 1991, 92, 95, 96, 97, 98, 99 Free Software Foundation, Inc. + * + * GLib is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or (at your option) any later version. + * + * GLib 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with GLib; see the file COPYING.LIB. If not, write + * to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + */ + +#include "config.h" + +#include <string.h> + +#include "gshell.h" + +#include "gslist.h" +#include "gstrfuncs.h" +#include "gstring.h" +#include "gtestutils.h" +#include "glibintl.h" + +/** + * SECTION: shell + * @title: Shell-related Utilities + * @short_description: shell-like commandline handling + **/ + +/** + * G_SHELL_ERROR: + * + * Error domain for shell functions. Errors in this domain will be from + * the #GShellError enumeration. See #GError for information on error + * domains. + **/ + +/** + * GShellError: + * @G_SHELL_ERROR_BAD_QUOTING: Mismatched or otherwise mangled quoting. + * @G_SHELL_ERROR_EMPTY_STRING: String to be parsed was empty. + * @G_SHELL_ERROR_FAILED: Some other error. + * + * Error codes returned by shell functions. + **/ +GQuark +g_shell_error_quark (void) +{ + return g_quark_from_static_string ("g-shell-error-quark"); +} + +/* Single quotes preserve the literal string exactly. escape + * sequences are not allowed; not even \' - if you want a ' + * in the quoted text, you have to do something like 'foo'\''bar' + * + * Double quotes allow $ ` " \ and newline to be escaped with backslash. + * Otherwise double quotes preserve things literally. + */ + +static gboolean +unquote_string_inplace (gchar* str, gchar** end, GError** err) +{ + gchar* dest; + gchar* s; + gchar quote_char; + + g_return_val_if_fail(end != NULL, FALSE); + g_return_val_if_fail(err == NULL || *err == NULL, FALSE); + g_return_val_if_fail(str != NULL, FALSE); + + dest = s = str; + + quote_char = *s; + + if (!(*s == '"' || *s == '\'')) + { + g_set_error_literal (err, + G_SHELL_ERROR, + G_SHELL_ERROR_BAD_QUOTING, + _("Quoted text doesn't begin with a quotation mark")); + *end = str; + return FALSE; + } + + /* Skip the initial quote mark */ + ++s; + + if (quote_char == '"') + { + while (*s) + { + g_assert(s > dest); /* loop invariant */ + + switch (*s) + { + case '"': + /* End of the string, return now */ + *dest = '\0'; + ++s; + *end = s; + return TRUE; + break; + + case '\\': + /* Possible escaped quote or \ */ + ++s; + switch (*s) + { + case '"': + case '\\': + case '`': + case '$': + case '\n': + *dest = *s; + ++s; + ++dest; + break; + + default: + /* not an escaped char */ + *dest = '\\'; + ++dest; + /* ++s already done. */ + break; + } + break; + + default: + *dest = *s; + ++dest; + ++s; + break; + } + + g_assert(s > dest); /* loop invariant */ + } + } + else + { + while (*s) + { + g_assert(s > dest); /* loop invariant */ + + if (*s == '\'') + { + /* End of the string, return now */ + *dest = '\0'; + ++s; + *end = s; + return TRUE; + } + else + { + *dest = *s; + ++dest; + ++s; + } + + g_assert(s > dest); /* loop invariant */ + } + } + + /* If we reach here this means the close quote was never encountered */ + + *dest = '\0'; + + g_set_error_literal (err, + G_SHELL_ERROR, + G_SHELL_ERROR_BAD_QUOTING, + _("Unmatched quotation mark in command line or other shell-quoted text")); + *end = s; + return FALSE; +} + +/** + * g_shell_quote: + * @unquoted_string: a literal string + * + * Quotes a string so that the shell (/bin/sh) will interpret the + * quoted string to mean @unquoted_string. If you pass a filename to + * the shell, for example, you should first quote it with this + * function. The return value must be freed with g_free(). The + * quoting style used is undefined (single or double quotes may be + * used). + * + * Return value: quoted string + **/ +gchar* +g_shell_quote (const gchar *unquoted_string) +{ + /* We always use single quotes, because the algorithm is cheesier. + * We could use double if we felt like it, that might be more + * human-readable. + */ + + const gchar *p; + GString *dest; + + g_return_val_if_fail (unquoted_string != NULL, NULL); + + dest = g_string_new ("'"); + + p = unquoted_string; + + /* could speed this up a lot by appending chunks of text at a + * time. + */ + while (*p) + { + /* Replace literal ' with a close ', a \', and a open ' */ + if (*p == '\'') + g_string_append (dest, "'\\''"); + else + g_string_append_c (dest, *p); + + ++p; + } + + /* close the quote */ + g_string_append_c (dest, '\''); + + return g_string_free (dest, FALSE); +} + +/** + * g_shell_unquote: + * @quoted_string: shell-quoted string + * @error: error return location or NULL + * + * Unquotes a string as the shell (/bin/sh) would. Only handles + * quotes; if a string contains file globs, arithmetic operators, + * variables, backticks, redirections, or other special-to-the-shell + * features, the result will be different from the result a real shell + * would produce (the variables, backticks, etc. will be passed + * through literally instead of being expanded). This function is + * guaranteed to succeed if applied to the result of + * g_shell_quote(). If it fails, it returns %NULL and sets the + * error. The @quoted_string need not actually contain quoted or + * escaped text; g_shell_unquote() simply goes through the string and + * unquotes/unescapes anything that the shell would. Both single and + * double quotes are handled, as are escapes including escaped + * newlines. The return value must be freed with g_free(). Possible + * errors are in the #G_SHELL_ERROR domain. + * + * Shell quoting rules are a bit strange. Single quotes preserve the + * literal string exactly. escape sequences are not allowed; not even + * \' - if you want a ' in the quoted text, you have to do something + * like 'foo'\''bar'. Double quotes allow $, `, ", \, and newline to + * be escaped with backslash. Otherwise double quotes preserve things + * literally. + * + * Return value: an unquoted string + **/ +gchar* +g_shell_unquote (const gchar *quoted_string, + GError **error) +{ + gchar *unquoted; + gchar *end; + gchar *start; + GString *retval; + + g_return_val_if_fail (quoted_string != NULL, NULL); + + unquoted = g_strdup (quoted_string); + + start = unquoted; + end = unquoted; + retval = g_string_new (NULL); + + /* The loop allows cases such as + * "foo"blah blah'bar'woo foo"baz"la la la\'\''foo' + */ + while (*start) + { + /* Append all non-quoted chars, honoring backslash escape + */ + + while (*start && !(*start == '"' || *start == '\'')) + { + if (*start == '\\') + { + /* all characters can get escaped by backslash, + * except newline, which is removed if it follows + * a backslash outside of quotes + */ + + ++start; + if (*start) + { + if (*start != '\n') + g_string_append_c (retval, *start); + ++start; + } + } + else + { + g_string_append_c (retval, *start); + ++start; + } + } + + if (*start) + { + if (!unquote_string_inplace (start, &end, error)) + { + goto error; + } + else + { + g_string_append (retval, start); + start = end; + } + } + } + + g_free (unquoted); + return g_string_free (retval, FALSE); + + error: + g_assert (error == NULL || *error != NULL); + + g_free (unquoted); + g_string_free (retval, TRUE); + return NULL; +} + +/* g_parse_argv() does a semi-arbitrary weird subset of the way + * the shell parses a command line. We don't do variable expansion, + * don't understand that operators are tokens, don't do tilde expansion, + * don't do command substitution, no arithmetic expansion, IFS gets ignored, + * don't do filename globs, don't remove redirection stuff, etc. + * + * READ THE UNIX98 SPEC on "Shell Command Language" before changing + * the behavior of this code. + * + * Steps to parsing the argv string: + * + * - tokenize the string (but since we ignore operators, + * our tokenization may diverge from what the shell would do) + * note that tokenization ignores the internals of a quoted + * word and it always splits on spaces, not on IFS even + * if we used IFS. We also ignore "end of input indicator" + * (I guess this is control-D?) + * + * Tokenization steps, from UNIX98 with operator stuff removed, + * are: + * + * 1) "If the current character is backslash, single-quote or + * double-quote (\, ' or ") and it is not quoted, it will affect + * quoting for subsequent characters up to the end of the quoted + * text. The rules for quoting are as described in Quoting + * . During token recognition no substitutions will be actually + * performed, and the result token will contain exactly the + * characters that appear in the input (except for newline + * character joining), unmodified, including any embedded or + * enclosing quotes or substitution operators, between the quote + * mark and the end of the quoted text. The token will not be + * delimited by the end of the quoted field." + * + * 2) "If the current character is an unquoted newline character, + * the current token will be delimited." + * + * 3) "If the current character is an unquoted blank character, any + * token containing the previous character is delimited and the + * current character will be discarded." + * + * 4) "If the previous character was part of a word, the current + * character will be appended to that word." + * + * 5) "If the current character is a "#", it and all subsequent + * characters up to, but excluding, the next newline character + * will be discarded as a comment. The newline character that + * ends the line is not considered part of the comment. The + * "#" starts a comment only when it is at the beginning of a + * token. Since the search for the end-of-comment does not + * consider an escaped newline character specially, a comment + * cannot be continued to the next line." + * + * 6) "The current character will be used as the start of a new word." + * + * + * - for each token (word), perform portions of word expansion, namely + * field splitting (using default whitespace IFS) and quote + * removal. Field splitting may increase the number of words. + * Quote removal does not increase the number of words. + * + * "If the complete expansion appropriate for a word results in an + * empty field, that empty field will be deleted from the list of + * fields that form the completely expanded command, unless the + * original word contained single-quote or double-quote characters." + * - UNIX98 spec + * + * + */ + +static inline void +ensure_token (GString **token) +{ + if (*token == NULL) + *token = g_string_new (NULL); +} + +static void +delimit_token (GString **token, + GSList **retval) +{ + if (*token == NULL) + return; + + *retval = g_slist_prepend (*retval, g_string_free (*token, FALSE)); + + *token = NULL; +} + +static GSList* +tokenize_command_line (const gchar *command_line, + GError **error) +{ + gchar current_quote; + const gchar *p; + GString *current_token = NULL; + GSList *retval = NULL; + gboolean quoted; + + current_quote = '\0'; + quoted = FALSE; + p = command_line; + + while (*p) + { + if (current_quote == '\\') + { + if (*p == '\n') + { + /* we append nothing; backslash-newline become nothing */ + } + else + { + /* we append the backslash and the current char, + * to be interpreted later after tokenization + */ + ensure_token (¤t_token); + g_string_append_c (current_token, '\\'); + g_string_append_c (current_token, *p); + } + + current_quote = '\0'; + } + else if (current_quote == '#') + { + /* Discard up to and including next newline */ + while (*p && *p != '\n') + ++p; + + current_quote = '\0'; + + if (*p == '\0') + break; + } + else if (current_quote) + { + if (*p == current_quote && + /* check that it isn't an escaped double quote */ + !(current_quote == '"' && quoted)) + { + /* close the quote */ + current_quote = '\0'; + } + + /* Everything inside quotes, and the close quote, + * gets appended literally. + */ + + ensure_token (¤t_token); + g_string_append_c (current_token, *p); + } + else + { + switch (*p) + { + case '\n': + delimit_token (¤t_token, &retval); + break; + + case ' ': + case '\t': + /* If the current token contains the previous char, delimit + * the current token. A nonzero length + * token should always contain the previous char. + */ + if (current_token && + current_token->len > 0) + { + delimit_token (¤t_token, &retval); + } + + /* discard all unquoted blanks (don't add them to a token) */ + break; + + + /* single/double quotes are appended to the token, + * escapes are maybe appended next time through the loop, + * comment chars are never appended. + */ + + case '\'': + case '"': + ensure_token (¤t_token); + g_string_append_c (current_token, *p); + + /* FALL THRU */ + + case '#': + case '\\': + current_quote = *p; + break; + + default: + /* Combines rules 4) and 6) - if we have a token, append to it, + * otherwise create a new token. + */ + ensure_token (¤t_token); + g_string_append_c (current_token, *p); + break; + } + } + + /* We need to count consecutive backslashes mod 2, + * to detect escaped doublequotes. + */ + if (*p != '\\') + quoted = FALSE; + else + quoted = !quoted; + + ++p; + } + + delimit_token (¤t_token, &retval); + + if (current_quote) + { + if (current_quote == '\\') + g_set_error (error, + G_SHELL_ERROR, + G_SHELL_ERROR_BAD_QUOTING, + _("Text ended just after a '\\' character." + " (The text was '%s')"), + command_line); + else + g_set_error (error, + G_SHELL_ERROR, + G_SHELL_ERROR_BAD_QUOTING, + _("Text ended before matching quote was found for %c." + " (The text was '%s')"), + current_quote, command_line); + + goto error; + } + + if (retval == NULL) + { + g_set_error_literal (error, + G_SHELL_ERROR, + G_SHELL_ERROR_EMPTY_STRING, + _("Text was empty (or contained only whitespace)")); + + goto error; + } + + /* we appended backward */ + retval = g_slist_reverse (retval); + + return retval; + + error: + g_assert (error == NULL || *error != NULL); + + if (retval) + { + g_slist_foreach (retval, (GFunc)g_free, NULL); + g_slist_free (retval); + } + + return NULL; +} + +/** + * g_shell_parse_argv: + * @command_line: command line to parse + * @argcp: return location for number of args + * @argvp: return location for array of args + * @error: return location for error + * + * Parses a command line into an argument vector, in much the same way + * the shell would, but without many of the expansions the shell would + * perform (variable expansion, globs, operators, filename expansion, + * etc. are not supported). The results are defined to be the same as + * those you would get from a UNIX98 /bin/sh, as long as the input + * contains none of the unsupported shell expansions. If the input + * does contain such expansions, they are passed through + * literally. Possible errors are those from the #G_SHELL_ERROR + * domain. Free the returned vector with g_strfreev(). + * + * Return value: %TRUE on success, %FALSE if error set + **/ +gboolean +g_shell_parse_argv (const gchar *command_line, + gint *argcp, + gchar ***argvp, + GError **error) +{ + /* Code based on poptParseArgvString() from libpopt */ + gint argc = 0; + gchar **argv = NULL; + GSList *tokens = NULL; + gint i; + GSList *tmp_list; + + g_return_val_if_fail (command_line != NULL, FALSE); + + tokens = tokenize_command_line (command_line, error); + if (tokens == NULL) + return FALSE; + + /* Because we can't have introduced any new blank space into the + * tokens (we didn't do any new expansions), we don't need to + * perform field splitting. If we were going to honor IFS or do any + * expansions, we would have to do field splitting on each word + * here. Also, if we were going to do any expansion we would need to + * remove any zero-length words that didn't contain quotes + * originally; but since there's no expansion we know all words have + * nonzero length, unless they contain quotes. + * + * So, we simply remove quotes, and don't do any field splitting or + * empty word removal, since we know there was no way to introduce + * such things. + */ + + argc = g_slist_length (tokens); + argv = g_new0 (gchar*, argc + 1); + i = 0; + tmp_list = tokens; + while (tmp_list) + { + argv[i] = g_shell_unquote (tmp_list->data, error); + + /* Since we already checked that quotes matched up in the + * tokenizer, this shouldn't be possible to reach I guess. + */ + if (argv[i] == NULL) + goto failed; + + tmp_list = g_slist_next (tmp_list); + ++i; + } + + g_slist_foreach (tokens, (GFunc)g_free, NULL); + g_slist_free (tokens); + + if (argcp) + *argcp = argc; + + if (argvp) + *argvp = argv; + else + g_strfreev (argv); + + return TRUE; + + failed: + + g_assert (error == NULL || *error != NULL); + g_strfreev (argv); + g_slist_foreach (tokens, (GFunc) g_free, NULL); + g_slist_free (tokens); + + return FALSE; +} |