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Diffstat (limited to 'gcc-4.2.1-5666.3/libiberty/make-relative-prefix.c')
| -rw-r--r-- | gcc-4.2.1-5666.3/libiberty/make-relative-prefix.c | 389 |
1 files changed, 389 insertions, 0 deletions
diff --git a/gcc-4.2.1-5666.3/libiberty/make-relative-prefix.c b/gcc-4.2.1-5666.3/libiberty/make-relative-prefix.c new file mode 100644 index 000000000..66ddcaa47 --- /dev/null +++ b/gcc-4.2.1-5666.3/libiberty/make-relative-prefix.c @@ -0,0 +1,389 @@ +/* Relative (relocatable) prefix support. + Copyright (C) 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, + 1999, 2000, 2001, 2002 Free Software Foundation, Inc. + +This file is part of libiberty. + +GCC 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. + +GCC 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 GCC; see the file COPYING. If not, write to the Free +Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA +02110-1301, USA. */ + +/* + +@deftypefn Extension {const char*} make_relative_prefix (const char *@var{progname}, const char *@var{bin_prefix}, const char *@var{prefix}) + +Given three paths @var{progname}, @var{bin_prefix}, @var{prefix}, +return the path that is in the same position relative to +@var{progname}'s directory as @var{prefix} is relative to +@var{bin_prefix}. That is, a string starting with the directory +portion of @var{progname}, followed by a relative pathname of the +difference between @var{bin_prefix} and @var{prefix}. + +If @var{progname} does not contain any directory separators, +@code{make_relative_prefix} will search @env{PATH} to find a program +named @var{progname}. Also, if @var{progname} is a symbolic link, +the symbolic link will be resolved. + +For example, if @var{bin_prefix} is @code{/alpha/beta/gamma/gcc/delta}, +@var{prefix} is @code{/alpha/beta/gamma/omega/}, and @var{progname} is +@code{/red/green/blue/gcc}, then this function will return +@code{/red/green/blue/../../omega/}. + +The return value is normally allocated via @code{malloc}. If no +relative prefix can be found, return @code{NULL}. + +@end deftypefn + +*/ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#ifdef HAVE_STDLIB_H +#include <stdlib.h> +#endif +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif + +#include <string.h> + +#include "ansidecl.h" +#include "libiberty.h" + +#ifndef R_OK +#define R_OK 4 +#define W_OK 2 +#define X_OK 1 +#endif + +#ifndef DIR_SEPARATOR +# define DIR_SEPARATOR '/' +#endif + +#if defined (_WIN32) || defined (__MSDOS__) \ + || defined (__DJGPP__) || defined (__OS2__) +# define HAVE_DOS_BASED_FILE_SYSTEM +# define HAVE_HOST_EXECUTABLE_SUFFIX +# define HOST_EXECUTABLE_SUFFIX ".exe" +# ifndef DIR_SEPARATOR_2 +# define DIR_SEPARATOR_2 '\\' +# endif +# define PATH_SEPARATOR ';' +#else +# define PATH_SEPARATOR ':' +#endif + +#ifndef DIR_SEPARATOR_2 +# define IS_DIR_SEPARATOR(ch) ((ch) == DIR_SEPARATOR) +#else +# define IS_DIR_SEPARATOR(ch) \ + (((ch) == DIR_SEPARATOR) || ((ch) == DIR_SEPARATOR_2)) +#endif + +#define DIR_UP ".." + +static char *save_string (const char *, int); +static char **split_directories (const char *, int *); +static void free_split_directories (char **); + +static char * +save_string (const char *s, int len) +{ + char *result = (char *) malloc (len + 1); + + memcpy (result, s, len); + result[len] = 0; + return result; +} + +/* Split a filename into component directories. */ + +static char ** +split_directories (const char *name, int *ptr_num_dirs) +{ + int num_dirs = 0; + char **dirs; + const char *p, *q; + int ch; + + /* Count the number of directories. Special case MSDOS disk names as part + of the initial directory. */ + p = name; +#ifdef HAVE_DOS_BASED_FILE_SYSTEM + if (name[1] == ':' && IS_DIR_SEPARATOR (name[2])) + { + p += 3; + num_dirs++; + } +#endif /* HAVE_DOS_BASED_FILE_SYSTEM */ + + while ((ch = *p++) != '\0') + { + if (IS_DIR_SEPARATOR (ch)) + { + num_dirs++; + while (IS_DIR_SEPARATOR (*p)) + p++; + } + } + + dirs = (char **) malloc (sizeof (char *) * (num_dirs + 2)); + if (dirs == NULL) + return NULL; + + /* Now copy the directory parts. */ + num_dirs = 0; + p = name; +#ifdef HAVE_DOS_BASED_FILE_SYSTEM + if (name[1] == ':' && IS_DIR_SEPARATOR (name[2])) + { + dirs[num_dirs++] = save_string (p, 3); + if (dirs[num_dirs - 1] == NULL) + { + free (dirs); + return NULL; + } + p += 3; + } +#endif /* HAVE_DOS_BASED_FILE_SYSTEM */ + + q = p; + while ((ch = *p++) != '\0') + { + if (IS_DIR_SEPARATOR (ch)) + { + while (IS_DIR_SEPARATOR (*p)) + p++; + + dirs[num_dirs++] = save_string (q, p - q); + if (dirs[num_dirs - 1] == NULL) + { + dirs[num_dirs] = NULL; + free_split_directories (dirs); + return NULL; + } + q = p; + } + } + + if (p - 1 - q > 0) + dirs[num_dirs++] = save_string (q, p - 1 - q); + dirs[num_dirs] = NULL; + + if (dirs[num_dirs - 1] == NULL) + { + free_split_directories (dirs); + return NULL; + } + + if (ptr_num_dirs) + *ptr_num_dirs = num_dirs; + return dirs; +} + +/* Release storage held by split directories. */ + +static void +free_split_directories (char **dirs) +{ + int i = 0; + + while (dirs[i] != NULL) + free (dirs[i++]); + + free ((char *) dirs); +} + +/* Given three strings PROGNAME, BIN_PREFIX, PREFIX, return a string that gets + to PREFIX starting with the directory portion of PROGNAME and a relative + pathname of the difference between BIN_PREFIX and PREFIX. + + For example, if BIN_PREFIX is /alpha/beta/gamma/gcc/delta, PREFIX is + /alpha/beta/gamma/omega/, and PROGNAME is /red/green/blue/gcc, then this + function will return /red/green/blue/../../omega/. + + If no relative prefix can be found, return NULL. */ + +char * +make_relative_prefix (const char *progname, + const char *bin_prefix, const char *prefix) +{ + char **prog_dirs, **bin_dirs, **prefix_dirs; + int prog_num, bin_num, prefix_num; + int i, n, common; + int needed_len; + char *ret, *ptr, *full_progname = NULL; + + if (progname == NULL || bin_prefix == NULL || prefix == NULL) + return NULL; + + /* If there is no full pathname, try to find the program by checking in each + of the directories specified in the PATH environment variable. */ + if (lbasename (progname) == progname) + { + char *temp; + + temp = getenv ("PATH"); + if (temp) + { + char *startp, *endp, *nstore; + size_t prefixlen = strlen (temp) + 1; + if (prefixlen < 2) + prefixlen = 2; + + nstore = (char *) alloca (prefixlen + strlen (progname) + 1); + + startp = endp = temp; + while (1) + { + if (*endp == PATH_SEPARATOR || *endp == 0) + { + if (endp == startp) + { + nstore[0] = '.'; + nstore[1] = DIR_SEPARATOR; + nstore[2] = '\0'; + } + else + { + strncpy (nstore, startp, endp - startp); + if (! IS_DIR_SEPARATOR (endp[-1])) + { + nstore[endp - startp] = DIR_SEPARATOR; + nstore[endp - startp + 1] = 0; + } + else + nstore[endp - startp] = 0; + } + strcat (nstore, progname); + if (! access (nstore, X_OK) +#ifdef HAVE_HOST_EXECUTABLE_SUFFIX + || ! access (strcat (nstore, HOST_EXECUTABLE_SUFFIX), X_OK) +#endif + ) + { + progname = nstore; + break; + } + + if (*endp == 0) + break; + endp = startp = endp + 1; + } + else + endp++; + } + } + } + + full_progname = lrealpath (progname); + if (full_progname == NULL) + return NULL; + + prog_dirs = split_directories (full_progname, &prog_num); + bin_dirs = split_directories (bin_prefix, &bin_num); + free (full_progname); + if (bin_dirs == NULL || prog_dirs == NULL) + return NULL; + + /* Remove the program name from comparison of directory names. */ + prog_num--; + + /* If we are still installed in the standard location, we don't need to + specify relative directories. Also, if argv[0] still doesn't contain + any directory specifiers after the search above, then there is not much + we can do. */ + if (prog_num == bin_num) + { + for (i = 0; i < bin_num; i++) + { + if (strcmp (prog_dirs[i], bin_dirs[i]) != 0) + break; + } + + if (prog_num <= 0 || i == bin_num) + { + free_split_directories (prog_dirs); + free_split_directories (bin_dirs); + prog_dirs = bin_dirs = (char **) 0; + return NULL; + } + } + + prefix_dirs = split_directories (prefix, &prefix_num); + if (prefix_dirs == NULL) + { + free_split_directories (prog_dirs); + free_split_directories (bin_dirs); + return NULL; + } + + /* Find how many directories are in common between bin_prefix & prefix. */ + n = (prefix_num < bin_num) ? prefix_num : bin_num; + for (common = 0; common < n; common++) + { + if (strcmp (bin_dirs[common], prefix_dirs[common]) != 0) + break; + } + + /* If there are no common directories, there can be no relative prefix. */ + if (common == 0) + { + free_split_directories (prog_dirs); + free_split_directories (bin_dirs); + free_split_directories (prefix_dirs); + return NULL; + } + + /* Two passes: first figure out the size of the result string, and + then construct it. */ + needed_len = 0; + for (i = 0; i < prog_num; i++) + needed_len += strlen (prog_dirs[i]); + needed_len += sizeof (DIR_UP) * (bin_num - common); + for (i = common; i < prefix_num; i++) + needed_len += strlen (prefix_dirs[i]); + needed_len += 1; /* Trailing NUL. */ + + ret = (char *) malloc (needed_len); + if (ret == NULL) + return NULL; + + /* Build up the pathnames in argv[0]. */ + *ret = '\0'; + for (i = 0; i < prog_num; i++) + strcat (ret, prog_dirs[i]); + + /* Now build up the ..'s. */ + ptr = ret + strlen(ret); + for (i = common; i < bin_num; i++) + { + strcpy (ptr, DIR_UP); + ptr += sizeof (DIR_UP) - 1; + *(ptr++) = DIR_SEPARATOR; + } + *ptr = '\0'; + + /* Put in directories to move over to prefix. */ + for (i = common; i < prefix_num; i++) + strcat (ret, prefix_dirs[i]); + + free_split_directories (prog_dirs); + free_split_directories (bin_dirs); + free_split_directories (prefix_dirs); + + return ret; +} |