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Diffstat (limited to 'src/expand_path.c')
| -rw-r--r-- | src/expand_path.c | 382 |
1 files changed, 382 insertions, 0 deletions
diff --git a/src/expand_path.c b/src/expand_path.c new file mode 100644 index 0000000..a25e84f --- /dev/null +++ b/src/expand_path.c @@ -0,0 +1,382 @@ +/* expand_path.c -- expand environmental variables in passed in string + * + * Copyright (C) 1995-2005 The Free Software Foundation, Inc. + * + * This program 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 2, or (at your option) + * any later version. + * + * This program 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. + * + * The main routine is expand_path(), it is the routine that handles + * the '~' character in four forms: + * ~name + * ~name/ + * ~/ + * ~ + * and handles environment variables contained within the pathname + * which are defined by: + * ${var_name} (var_name is the name of the environ variable) + * $var_name (var_name ends w/ non-alphanumeric char other than '_') + */ + +#include "cvs.h" +#include <sys/types.h> + +/* User variables. */ + +List *variable_list; + +static void variable_delproc (Node *); + +static void +variable_delproc (Node *node) +{ + free (node->data); +} + +/* Currently used by -s option; we might want a way to set user + variables in a file in the $CVSROOT/CVSROOT directory too. */ + +void +variable_set (char *nameval) +{ + char *p; + char *name; + Node *node; + + p = nameval; + while (isalnum ((unsigned char) *p) || *p == '_') + ++p; + if (*p != '=') + error (1, 0, "invalid character in user variable name in %s", nameval); + if (p == nameval) + error (1, 0, "empty user variable name in %s", nameval); + name = xmalloc (p - nameval + 1); + strncpy (name, nameval, p - nameval); + name[p - nameval] = '\0'; + /* Make p point to the value. */ + ++p; + if (strchr (p, '\012')) + error (1, 0, "linefeed in user variable value in %s", nameval); + + if (!variable_list) + variable_list = getlist (); + + node = findnode (variable_list, name); + if (!node) + { + node = getnode (); + node->type = VARIABLE; + node->delproc = variable_delproc; + node->key = name; + node->data = xstrdup (p); + (void) addnode (variable_list, node); + } + else + { + /* Replace the old value. For example, this means that -s + options on the command line override ones from .cvsrc. */ + free (node->data); + node->data = xstrdup (p); + free (name); + } +} + + + +/* Expand variable NAME into its contents, per the rules above. + * + * CVSROOT is used to expanding $CVSROOT. + * + * RETURNS + * A pointer to the requested variable contents or NULL when the requested + * variable is not found. + * + * ERRORS + * None, though this function may generate warning messages when NAME is not + * found. + */ +static const char * +expand_variable (const char *name, const char *cvsroot, + const char *file, int line) +{ + if (!strcmp (name, CVSROOT_ENV)) + return cvsroot; + else if (!strcmp (name, "RCSBIN")) + { + error (0, 0, "RCSBIN internal variable is no longer supported"); + return NULL; + } + else if (!strcmp (name, EDITOR1_ENV)) + return Editor; + else if (!strcmp (name, EDITOR2_ENV)) + return Editor; + else if (!strcmp (name, EDITOR3_ENV)) + return Editor; + else if (!strcmp (name, "USER")) + return getcaller (); + else if (!strcmp (name, "SESSIONID") + || !strcmp (name, "COMMITID")) + return global_session_id; + else if (isalpha (name[0])) + { + /* These names are reserved for future versions of CVS, + so that is why it is an error. */ + if (line) + error (0, 0, "%s:%d: no such internal variable $%s", + file, line, name); + else + error (0, 0, "%s: no such internal variable $%s", + file, name); + return NULL; + } + else if (name[0] == '=') + { + Node *node; + /* Crazy syntax for a user variable. But we want + *something* that lets the user name a user variable + anything he wants, without interference from + (existing or future) internal variables. */ + node = findnode (variable_list, name + 1); + if (!node) + { + if (line) + error (0, 0, "%s:%d: no such user variable ${%s}", + file, line, name); + else + error (0, 0, "%s: no such user variable ${%s}", + file, name); + return NULL; + } + return node->data; + } + else + { + /* It is an unrecognized character. We return an error to + reserve these for future versions of CVS; it is plausible + that various crazy syntaxes might be invented for inserting + information about revisions, branches, etc. */ + if (line) + error (0, 0, "%s:%d: unrecognized variable syntax %s", + file, line, name); + else + error (0, 0, "%s: unrecognized variable syntax %s", + file, name); + return NULL; + } +} + + + +/* This routine will expand the pathname to account for ~ and $ + * characters as described above. Returns a pointer to a newly + * malloc'd string. If an error occurs, an error message is printed + * via error() and NULL is returned. FILE and LINE are the filename + * and linenumber to include in the error message. FILE must point + * to something; LINE can be zero to indicate the line number is not + * known. + * + * When FORMATSAFE is set, percent signs (`%') in variable contents are doubled + * to prevent later expansion by format_cmdline. + * + * CVSROOT is used to expanding $CVSROOT. + */ +char * +expand_path (const char *name, const char *cvsroot, bool formatsafe, + const char *file, int line) +{ + size_t s, d, p; + const char *e; + + char *mybuf = NULL; + size_t mybuf_size = 0; + char *buf = NULL; + size_t buf_size = 0; + + char inquotes = '\0'; + + char *result; + + /* Sorry this routine is so ugly; it is a head-on collision + between the `traditional' unix *d++ style and the need to + dynamically allocate. It would be much cleaner (and probably + faster, not that this is a bottleneck for CVS) with more use of + strcpy & friends, but I haven't taken the effort to rewrite it + thusly. */ + + /* First copy from NAME to MYBUF, expanding $<foo> as we go. */ + s = d = 0; + expand_string (&mybuf, &mybuf_size, d + 1); + while ((mybuf[d++] = name[s]) != '\0') + { + if (name[s] == '\\') + { + /* The next character is a literal. Leave the \ in the string + * since it will be needed again when the string is split into + * arguments. + */ + /* if we have a \ as the last character of the string, just leave + * it there - this is where we would set the escape flag to tell + * our parent we want another line if we cared. + */ + if (name[++s]) + { + expand_string (&mybuf, &mybuf_size, d + 1); + mybuf[d++] = name[s++]; + } + } + /* skip $ variable processing for text inside single quotes */ + else if (inquotes == '\'') + { + if (name[s++] == '\'') + { + inquotes = '\0'; + } + } + else if (name[s] == '\'') + { + s++; + inquotes = '\''; + } + else if (name[s] == '"') + { + s++; + if (inquotes) inquotes = '\0'; + else inquotes = '"'; + } + else if (name[s++] == '$') + { + int flag = (name[s] == '{'); + p = d; + + expand_string (&mybuf, &mybuf_size, d + 1); + for (; (mybuf[d++] = name[s]); s++) + { + if (flag + ? name[s] =='}' + : !isalnum (name[s]) && name[s] != '_') + break; + expand_string (&mybuf, &mybuf_size, d + 1); + } + mybuf[--d] = '\0'; + e = expand_variable (&mybuf[p+flag], cvsroot, file, line); + + if (e) + { + expand_string (&mybuf, &mybuf_size, d + 1); + for (d = p - 1; (mybuf[d++] = *e++); ) + { + expand_string (&mybuf, &mybuf_size, d + 1); + if (mybuf[d-1] == '"') + { + /* escape the double quotes if we're between a matched + * pair of double quotes so that this sub will be + * passed inside as or as part of a single argument + * during the argument split later. + */ + if (inquotes) + { + mybuf[d-1] = '\\'; + expand_string (&mybuf, &mybuf_size, d + 1); + mybuf[d++] = '"'; + } + } + else if (formatsafe && mybuf[d-1] == '%') + { + /* escape '%' to get past printf style format strings + * later (in make_cmdline). + */ + expand_string (&mybuf, &mybuf_size, d + 1); + mybuf[d] = '%'; + d++; + } + } + --d; + if (flag && name[s]) + s++; + } + else + /* expand_variable has already printed an error message. */ + goto error_exit; + } + expand_string (&mybuf, &mybuf_size, d + 1); + } + expand_string (&mybuf, &mybuf_size, d + 1); + mybuf[d] = '\0'; + + /* Then copy from MYBUF to BUF, expanding ~. */ + s = d = 0; + /* If you don't want ~username ~/ to be expanded simply remove + * This entire if statement including the else portion + */ + if (mybuf[s] == '~') + { + p = d; + while (mybuf[++s] != '/' && mybuf[s] != '\0') + { + expand_string (&buf, &buf_size, p + 1); + buf[p++] = name[s]; + } + expand_string (&buf, &buf_size, p + 1); + buf[p] = '\0'; + + if (p == d) + e = get_homedir (); + else + { +#ifdef GETPWNAM_MISSING + if (line) + error (0, 0, + "%s:%d:tilde expansion not supported on this system", + file, line); + else + error (0, 0, "%s:tilde expansion not supported on this system", + file); + goto error_exit; +#else + struct passwd *ps; + ps = getpwnam (buf + d); + if (ps == NULL) + { + if (line) + error (0, 0, "%s:%d: no such user %s", + file, line, buf + d); + else + error (0, 0, "%s: no such user %s", file, buf + d); + goto error_exit; + } + e = ps->pw_dir; +#endif + } + if (!e) + error (1, 0, "cannot find home directory"); + + p = strlen (e); + expand_string (&buf, &buf_size, d + p); + memcpy (buf + d, e, p); + d += p; + } + /* Kill up to here */ + p = strlen (mybuf + s) + 1; + expand_string (&buf, &buf_size, d + p); + memcpy (buf + d, mybuf + s, p); + + /* OK, buf contains the value we want to return. Clean up and return + it. */ + free (mybuf); + /* Save a little memory with xstrdup; buf will tend to allocate + more than it needs to. */ + result = xstrdup (buf); + free (buf); + return result; + + error_exit: + if (mybuf) free (mybuf); + if (buf) free (buf); + return NULL; +} |