diff options
Diffstat (limited to 'libcpp/files.c')
| -rw-r--r-- | libcpp/files.c | 1827 |
1 files changed, 1827 insertions, 0 deletions
diff --git a/libcpp/files.c b/libcpp/files.c new file mode 100644 index 000000000..456c0b0f1 --- /dev/null +++ b/libcpp/files.c @@ -0,0 +1,1827 @@ +/* Part of CPP library. File handling. + Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1998, + 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 + Free Software Foundation, Inc. + Written by Per Bothner, 1994. + Based on CCCP program by Paul Rubin, June 1986 + Adapted to ANSI C, Richard Stallman, Jan 1987 + Split out of cpplib.c, Zack Weinberg, Oct 1998 + Reimplemented, Neil Booth, Jul 2003 + +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 3, 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. + +You should have received a copy of the GNU General Public License +along with this program; see the file COPYING3. If not see +<http://www.gnu.org/licenses/>. */ + +#include "config.h" +#include "system.h" +#include "cpplib.h" +#include "internal.h" +#include "mkdeps.h" +#include "obstack.h" +#include "hashtab.h" +#include "md5.h" +#include <dirent.h> + +/* Variable length record files on VMS will have a stat size that includes + record control characters that won't be included in the read size. */ +#ifdef VMS +# define FAB_C_VAR 2 /* variable length records (see Starlet fabdef.h) */ +# define STAT_SIZE_RELIABLE(ST) ((ST).st_fab_rfm != FAB_C_VAR) +#else +# define STAT_SIZE_RELIABLE(ST) true +#endif + +#ifdef __DJGPP__ +#include <io.h> + /* For DJGPP redirected input is opened in text mode. */ +# define set_stdin_to_binary_mode() \ + if (! isatty (0)) setmode (0, O_BINARY) +#else +# define set_stdin_to_binary_mode() /* Nothing */ +#endif + +/* This structure represents a file searched for by CPP, whether it + exists or not. An instance may be pointed to by more than one + file_hash_entry; at present no reference count is kept. */ +struct _cpp_file +{ + /* Filename as given to #include or command line switch. */ + const char *name; + + /* The full path used to find the file. */ + const char *path; + + /* The full path of the pch file. */ + const char *pchname; + + /* The file's path with the basename stripped. NULL if it hasn't + been calculated yet. */ + const char *dir_name; + + /* Chain through all files. */ + struct _cpp_file *next_file; + + /* The contents of NAME after calling read_file(). */ + const uchar *buffer; + + /* Pointer to the real start of BUFFER. read_file() might increment + BUFFER; when freeing, this this pointer must be used instead. */ + const uchar *buffer_start; + + /* The macro, if any, preventing re-inclusion. */ + const cpp_hashnode *cmacro; + + /* The directory in the search path where FILE was found. Used for + #include_next and determining whether a header is a system + header. */ + cpp_dir *dir; + + /* As filled in by stat(2) for the file. */ + struct stat st; + + /* File descriptor. Invalid if -1, otherwise open. */ + int fd; + + /* Zero if this file was successfully opened and stat()-ed, + otherwise errno obtained from failure. */ + int err_no; + + /* Number of times the file has been stacked for preprocessing. */ + unsigned short stack_count; + + /* If opened with #import or contains #pragma once. */ + bool once_only; + + /* If read() failed before. */ + bool dont_read; + + /* If this file is the main file. */ + bool main_file; + + /* If BUFFER above contains the true contents of the file. */ + bool buffer_valid; +}; + +/* A singly-linked list for all searches for a given file name, with + its head pointed to by a slot in FILE_HASH. The file name is what + appeared between the quotes in a #include directive; it can be + determined implicitly from the hash table location or explicitly + from FILE->name. + + FILE is a structure containing details about the file that was + found with that search, or details of how the search failed. + + START_DIR is the starting location of the search in the include + chain. The current directories for "" includes are also hashed in + the hash table and therefore unique. Files that are looked up + without using a search path, such as absolute filenames and file + names from the command line share a special starting directory so + they don't cause cache hits with normal include-chain lookups. + + If START_DIR is NULL then the entry is for a directory, not a file, + and the directory is in DIR. Since the starting point in a file + lookup chain is never NULL, this means that simple pointer + comparisons against START_DIR can be made to determine cache hits + in file lookups. + + If a cache lookup fails because of e.g. an extra "./" in the path, + then nothing will break. It is just less efficient as CPP will + have to do more work re-preprocessing the file, and/or comparing + its contents against earlier once-only files. +*/ +struct file_hash_entry +{ + struct file_hash_entry *next; + cpp_dir *start_dir; + source_location location; + union + { + _cpp_file *file; + cpp_dir *dir; + } u; +}; + +/* Number of entries to put in a file_hash_entry pool. */ +#define FILE_HASH_POOL_SIZE 127 + +/* A file hash entry pool. We allocate file_hash_entry object from + one of these. */ +struct file_hash_entry_pool +{ + /* Number of entries used from this pool. */ + unsigned int file_hash_entries_used; + /* Next pool in the chain; used when freeing. */ + struct file_hash_entry_pool *next; + /* The memory pool. */ + struct file_hash_entry pool[FILE_HASH_POOL_SIZE]; +}; + +static bool open_file (_cpp_file *file); +static bool pch_open_file (cpp_reader *pfile, _cpp_file *file, + bool *invalid_pch); +static bool find_file_in_dir (cpp_reader *pfile, _cpp_file *file, + bool *invalid_pch); +static bool read_file_guts (cpp_reader *pfile, _cpp_file *file); +static bool read_file (cpp_reader *pfile, _cpp_file *file); +static bool should_stack_file (cpp_reader *, _cpp_file *file, bool import); +static struct cpp_dir *search_path_head (cpp_reader *, const char *fname, + int angle_brackets, enum include_type); +static const char *dir_name_of_file (_cpp_file *file); +static void open_file_failed (cpp_reader *pfile, _cpp_file *file, int); +static struct file_hash_entry *search_cache (struct file_hash_entry *head, + const cpp_dir *start_dir); +static _cpp_file *make_cpp_file (cpp_reader *, cpp_dir *, const char *fname); +static void destroy_cpp_file (_cpp_file *); +static cpp_dir *make_cpp_dir (cpp_reader *, const char *dir_name, int sysp); +static void allocate_file_hash_entries (cpp_reader *pfile); +static struct file_hash_entry *new_file_hash_entry (cpp_reader *pfile); +static int report_missing_guard (void **slot, void *b); +static hashval_t file_hash_hash (const void *p); +static int file_hash_eq (const void *p, const void *q); +static char *read_filename_string (int ch, FILE *f); +static void read_name_map (cpp_dir *dir); +static char *remap_filename (cpp_reader *pfile, _cpp_file *file); +static char *append_file_to_dir (const char *fname, cpp_dir *dir); +static bool validate_pch (cpp_reader *, _cpp_file *file, const char *pchname); +static int pchf_save_compare (const void *e1, const void *e2); +static int pchf_compare (const void *d_p, const void *e_p); +static bool check_file_against_entries (cpp_reader *, _cpp_file *, bool); + +/* Given a filename in FILE->PATH, with the empty string interpreted + as <stdin>, open it. + + On success FILE contains an open file descriptor and stat + information for the file. On failure the file descriptor is -1 and + the appropriate errno is also stored in FILE. Returns TRUE iff + successful. + + We used to open files in nonblocking mode, but that caused more + problems than it solved. Do take care not to acquire a controlling + terminal by mistake (this can't happen on sane systems, but + paranoia is a virtue). + + Use the three-argument form of open even though we aren't + specifying O_CREAT, to defend against broken system headers. + + O_BINARY tells some runtime libraries (notably DJGPP) not to do + newline translation; we can handle DOS line breaks just fine + ourselves. */ +static bool +open_file (_cpp_file *file) +{ + if (file->path[0] == '\0') + { + file->fd = 0; + set_stdin_to_binary_mode (); + } + else + file->fd = open (file->path, O_RDONLY | O_NOCTTY | O_BINARY, 0666); + + if (file->fd != -1) + { + if (fstat (file->fd, &file->st) == 0) + { + if (!S_ISDIR (file->st.st_mode)) + { + file->err_no = 0; + return true; + } + + /* Ignore a directory and continue the search. The file we're + looking for may be elsewhere in the search path. */ + errno = ENOENT; + } + + close (file->fd); + file->fd = -1; + } +#if defined(_WIN32) && !defined(__CYGWIN__) + else if (errno == EACCES) + { + /* On most UNIX systems, open succeeds on a directory. Above, + we check if we have opened a directory and if so, set errno + to ENOENT. However, on Windows, opening a directory + fails with EACCES. We want to return ENOENT in that + case too. */ + if (stat (file->path, &file->st) == 0 + && S_ISDIR (file->st.st_mode)) + errno = ENOENT; + else + /* The call to stat may have reset errno. */ + errno = EACCES; + } +#endif + else if (errno == ENOTDIR) + errno = ENOENT; + + file->err_no = errno; + + return false; +} + +/* Temporary PCH intercept of opening a file. Try to find a PCH file + based on FILE->name and FILE->dir, and test those found for + validity using PFILE->cb.valid_pch. Return true iff a valid file is + found. Set *INVALID_PCH if a PCH file is found but wasn't valid. */ + +static bool +pch_open_file (cpp_reader *pfile, _cpp_file *file, bool *invalid_pch) +{ + static const char extension[] = ".gch"; + const char *path = file->path; + size_t len, flen; + char *pchname; + struct stat st; + bool valid = false; + + /* No PCH on <stdin> or if not requested. */ + if (file->name[0] == '\0' || !pfile->cb.valid_pch) + return false; + + /* If the file is not included as first include from either the toplevel + file or the command-line it is not a valid use of PCH. */ + if (pfile->all_files + && pfile->all_files->next_file) + return false; + + flen = strlen (path); + len = flen + sizeof (extension); + pchname = XNEWVEC (char, len); + memcpy (pchname, path, flen); + memcpy (pchname + flen, extension, sizeof (extension)); + + if (stat (pchname, &st) == 0) + { + DIR *pchdir; + struct dirent *d; + size_t dlen, plen = len; + + if (!S_ISDIR (st.st_mode)) + valid = validate_pch (pfile, file, pchname); + else if ((pchdir = opendir (pchname)) != NULL) + { + pchname[plen - 1] = '/'; + while ((d = readdir (pchdir)) != NULL) + { + dlen = strlen (d->d_name) + 1; + if ((strcmp (d->d_name, ".") == 0) + || (strcmp (d->d_name, "..") == 0)) + continue; + if (dlen + plen > len) + { + len += dlen + 64; + pchname = XRESIZEVEC (char, pchname, len); + } + memcpy (pchname + plen, d->d_name, dlen); + valid = validate_pch (pfile, file, pchname); + if (valid) + break; + } + closedir (pchdir); + } + if (!valid) + *invalid_pch = true; + } + + if (valid) + file->pchname = pchname; + else + free (pchname); + + return valid; +} + +/* Try to open the path FILE->name appended to FILE->dir. This is + where remap and PCH intercept the file lookup process. Return true + if the file was found, whether or not the open was successful. + Set *INVALID_PCH to true if a PCH file is found but wasn't valid. */ + +static bool +find_file_in_dir (cpp_reader *pfile, _cpp_file *file, bool *invalid_pch) +{ + char *path; + + if (CPP_OPTION (pfile, remap) && (path = remap_filename (pfile, file))) + ; + else + if (file->dir->construct) + path = file->dir->construct (file->name, file->dir); + else + path = append_file_to_dir (file->name, file->dir); + + if (path) + { + hashval_t hv = htab_hash_string (path); + char *copy; + void **pp; + + if (htab_find_with_hash (pfile->nonexistent_file_hash, path, hv) != NULL) + { + file->err_no = ENOENT; + return false; + } + + file->path = path; + if (pch_open_file (pfile, file, invalid_pch)) + return true; + + if (open_file (file)) + return true; + + if (file->err_no != ENOENT) + { + open_file_failed (pfile, file, 0); + return true; + } + + /* We copy the path name onto an obstack partly so that we don't + leak the memory, but mostly so that we don't fragment the + heap. */ + copy = (char *) obstack_copy0 (&pfile->nonexistent_file_ob, path, + strlen (path)); + free (path); + pp = htab_find_slot_with_hash (pfile->nonexistent_file_hash, + copy, hv, INSERT); + *pp = copy; + + file->path = file->name; + } + else + { + file->err_no = ENOENT; + file->path = NULL; + } + + return false; +} + +/* Return tue iff the missing_header callback found the given HEADER. */ +static bool +search_path_exhausted (cpp_reader *pfile, const char *header, _cpp_file *file) +{ + missing_header_cb func = pfile->cb.missing_header; + + /* When the regular search path doesn't work, try context dependent + headers search paths. */ + if (func + && file->dir == NULL) + { + if ((file->path = func (pfile, header, &file->dir)) != NULL) + { + if (open_file (file)) + return true; + free ((void *)file->path); + } + file->path = file->name; + } + + return false; +} + +bool +_cpp_find_failed (_cpp_file *file) +{ + return file->err_no != 0; +} + +/* Given a filename FNAME search for such a file in the include path + starting from START_DIR. If FNAME is the empty string it is + interpreted as STDIN if START_DIR is PFILE->no_search_path. + + If the file is not found in the file cache fall back to the O/S and + add the result to our cache. + + If the file was not found in the filesystem, or there was an error + opening it, then ERR_NO is nonzero and FD is -1. If the file was + found, then ERR_NO is zero and FD could be -1 or an open file + descriptor. FD can be -1 if the file was found in the cache and + had previously been closed. To open it again pass the return value + to open_file(). +*/ +_cpp_file * +_cpp_find_file (cpp_reader *pfile, const char *fname, cpp_dir *start_dir, bool fake, int angle_brackets) +{ + struct file_hash_entry *entry, **hash_slot; + _cpp_file *file; + bool invalid_pch = false; + bool saw_bracket_include = false; + bool saw_quote_include = false; + struct cpp_dir *found_in_cache = NULL; + + /* Ensure we get no confusion between cached files and directories. */ + if (start_dir == NULL) + cpp_error (pfile, CPP_DL_ICE, "NULL directory in find_file"); + + hash_slot = (struct file_hash_entry **) + htab_find_slot_with_hash (pfile->file_hash, fname, + htab_hash_string (fname), + INSERT); + + /* First check the cache before we resort to memory allocation. */ + entry = search_cache (*hash_slot, start_dir); + if (entry) + return entry->u.file; + + file = make_cpp_file (pfile, start_dir, fname); + + /* Try each path in the include chain. */ + for (; !fake ;) + { + if (find_file_in_dir (pfile, file, &invalid_pch)) + break; + + file->dir = file->dir->next; + if (file->dir == NULL) + { + if (search_path_exhausted (pfile, fname, file)) + { + /* Although this file must not go in the cache, because + the file found might depend on things (like the current file) + that aren't represented in the cache, it still has to go in + the list of all files so that #import works. */ + file->next_file = pfile->all_files; + pfile->all_files = file; + return file; + } + + if (invalid_pch) + { + cpp_error (pfile, CPP_DL_ERROR, + "one or more PCH files were found, but they were invalid"); + if (!cpp_get_options (pfile)->warn_invalid_pch) + cpp_error (pfile, CPP_DL_ERROR, + "use -Winvalid-pch for more information"); + } + open_file_failed (pfile, file, angle_brackets); + break; + } + + /* Only check the cache for the starting location (done above) + and the quote and bracket chain heads because there are no + other possible starting points for searches. */ + if (file->dir == pfile->bracket_include) + saw_bracket_include = true; + else if (file->dir == pfile->quote_include) + saw_quote_include = true; + else + continue; + + entry = search_cache (*hash_slot, file->dir); + if (entry) + { + found_in_cache = file->dir; + break; + } + } + + if (entry) + { + /* Cache for START_DIR too, sharing the _cpp_file structure. */ + free ((char *) file->name); + free (file); + file = entry->u.file; + } + else + { + /* This is a new file; put it in the list. */ + file->next_file = pfile->all_files; + pfile->all_files = file; + } + + /* Store this new result in the hash table. */ + entry = new_file_hash_entry (pfile); + entry->next = *hash_slot; + entry->start_dir = start_dir; + entry->location = pfile->line_table->highest_location; + entry->u.file = file; + *hash_slot = entry; + + /* If we passed the quote or bracket chain heads, cache them also. + This speeds up processing if there are lots of -I options. */ + if (saw_bracket_include + && pfile->bracket_include != start_dir + && found_in_cache != pfile->bracket_include) + { + entry = new_file_hash_entry (pfile); + entry->next = *hash_slot; + entry->start_dir = pfile->bracket_include; + entry->location = pfile->line_table->highest_location; + entry->u.file = file; + *hash_slot = entry; + } + if (saw_quote_include + && pfile->quote_include != start_dir + && found_in_cache != pfile->quote_include) + { + entry = new_file_hash_entry (pfile); + entry->next = *hash_slot; + entry->start_dir = pfile->quote_include; + entry->location = pfile->line_table->highest_location; + entry->u.file = file; + *hash_slot = entry; + } + + return file; +} + +/* Read a file into FILE->buffer, returning true on success. + + If FILE->fd is something weird, like a block device, we don't want + to read it at all. Don't even try to figure out what something is, + except for plain files and block devices, since there is no + reliable portable way of doing this. + + FIXME: Flush file cache and try again if we run out of memory. */ +static bool +read_file_guts (cpp_reader *pfile, _cpp_file *file) +{ + ssize_t size, total, count; + uchar *buf; + bool regular; + + if (S_ISBLK (file->st.st_mode)) + { + cpp_error (pfile, CPP_DL_ERROR, "%s is a block device", file->path); + return false; + } + + regular = S_ISREG (file->st.st_mode); + if (regular) + { + /* off_t might have a wider range than ssize_t - in other words, + the max size of a file might be bigger than the address + space. We can't handle a file that large. (Anyone with + a single source file bigger than 2GB needs to rethink + their coding style.) Some systems (e.g. AIX 4.1) define + SSIZE_MAX to be much smaller than the actual range of the + type. Use INTTYPE_MAXIMUM unconditionally to ensure this + does not bite us. */ + if (file->st.st_size > INTTYPE_MAXIMUM (ssize_t)) + { + cpp_error (pfile, CPP_DL_ERROR, "%s is too large", file->path); + return false; + } + + size = file->st.st_size; + } + else + /* 8 kilobytes is a sensible starting size. It ought to be bigger + than the kernel pipe buffer, and it's definitely bigger than + the majority of C source files. */ + size = 8 * 1024; + + buf = XNEWVEC (uchar, size + 1); + total = 0; + while ((count = read (file->fd, buf + total, size - total)) > 0) + { + total += count; + + if (total == size) + { + if (regular) + break; + size *= 2; + buf = XRESIZEVEC (uchar, buf, size + 1); + } + } + + if (count < 0) + { + cpp_errno (pfile, CPP_DL_ERROR, file->path); + return false; + } + + if (regular && total != size && STAT_SIZE_RELIABLE (file->st)) + cpp_error (pfile, CPP_DL_WARNING, + "%s is shorter than expected", file->path); + + file->buffer = _cpp_convert_input (pfile, + CPP_OPTION (pfile, input_charset), + buf, size, total, + &file->buffer_start, + &file->st.st_size); + file->buffer_valid = true; + + return true; +} + +/* Convenience wrapper around read_file_guts that opens the file if + necessary and closes the file descriptor after reading. FILE must + have been passed through find_file() at some stage. */ +static bool +read_file (cpp_reader *pfile, _cpp_file *file) +{ + /* If we already have its contents in memory, succeed immediately. */ + if (file->buffer_valid) + return true; + + /* If an earlier read failed for some reason don't try again. */ + if (file->dont_read || file->err_no) + return false; + + if (file->fd == -1 && !open_file (file)) + { + open_file_failed (pfile, file, 0); + return false; + } + + file->dont_read = !read_file_guts (pfile, file); + close (file->fd); + file->fd = -1; + + return !file->dont_read; +} + +/* Returns TRUE if FILE's contents have been successfully placed in + FILE->buffer and the file should be stacked, otherwise false. */ +static bool +should_stack_file (cpp_reader *pfile, _cpp_file *file, bool import) +{ + _cpp_file *f; + + /* Skip once-only files. */ + if (file->once_only) + return false; + + /* We must mark the file once-only if #import now, before header + guard checks. Otherwise, undefining the header guard might + cause the file to be re-stacked. */ + if (import) + { + _cpp_mark_file_once_only (pfile, file); + + /* Don't stack files that have been stacked before. */ + if (file->stack_count) + return false; + } + + /* Skip if the file had a header guard and the macro is defined. + PCH relies on this appearing before the PCH handler below. */ + if (file->cmacro && file->cmacro->type == NT_MACRO) + return false; + + /* Handle PCH files immediately; don't stack them. */ + if (file->pchname) + { + pfile->cb.read_pch (pfile, file->pchname, file->fd, file->path); + file->fd = -1; + free ((void *) file->pchname); + file->pchname = NULL; + return false; + } + + if (!read_file (pfile, file)) + return false; + + /* Check the file against the PCH file. This is done before + checking against files we've already seen, since it may save on + I/O. */ + if (check_file_against_entries (pfile, file, import)) + { + /* If this isn't a #import, but yet we can't include the file, + that means that it was #import-ed in the PCH file, + so we can never include it again. */ + if (! import) + _cpp_mark_file_once_only (pfile, file); + return false; + } + + /* Now we've read the file's contents, we can stack it if there + are no once-only files. */ + if (!pfile->seen_once_only) + return true; + + /* We may have read the file under a different name. Look + for likely candidates and compare file contents to be sure. */ + for (f = pfile->all_files; f; f = f->next_file) + { + if (f == file) + continue; + + if ((import || f->once_only) + && f->err_no == 0 + && f->st.st_mtime == file->st.st_mtime + && f->st.st_size == file->st.st_size) + { + _cpp_file *ref_file; + bool same_file_p = false; + + if (f->buffer && !f->buffer_valid) + { + /* We already have a buffer but it is not valid, because + the file is still stacked. Make a new one. */ + ref_file = make_cpp_file (pfile, f->dir, f->name); + ref_file->path = f->path; + } + else + /* The file is not stacked anymore. We can reuse it. */ + ref_file = f; + + same_file_p = read_file (pfile, ref_file) + /* Size might have changed in read_file(). */ + && ref_file->st.st_size == file->st.st_size + && !memcmp (ref_file->buffer, + file->buffer, + file->st.st_size); + + if (f->buffer && !f->buffer_valid) + { + ref_file->path = 0; + destroy_cpp_file (ref_file); + } + + if (same_file_p) + break; + } + } + + return f == NULL; +} + +/* Place the file referenced by FILE into a new buffer on the buffer + stack if possible. IMPORT is true if this stacking attempt is + because of a #import directive. Returns true if a buffer is + stacked. */ +bool +_cpp_stack_file (cpp_reader *pfile, _cpp_file *file, bool import) +{ + cpp_buffer *buffer; + int sysp; + + if (!should_stack_file (pfile, file, import)) + return false; + + if (pfile->buffer == NULL || file->dir == NULL) + sysp = 0; + else + sysp = MAX (pfile->buffer->sysp, file->dir->sysp); + + /* Add the file to the dependencies on its first inclusion. */ + if (CPP_OPTION (pfile, deps.style) > !!sysp && !file->stack_count) + { + if (!file->main_file || !CPP_OPTION (pfile, deps.ignore_main_file)) + deps_add_dep (pfile->deps, file->path); + } + + /* Clear buffer_valid since _cpp_clean_line messes it up. */ + file->buffer_valid = false; + file->stack_count++; + + /* Stack the buffer. */ + buffer = cpp_push_buffer (pfile, file->buffer, file->st.st_size, + CPP_OPTION (pfile, preprocessed) + && !CPP_OPTION (pfile, directives_only)); + buffer->file = file; + buffer->sysp = sysp; + + /* Initialize controlling macro state. */ + pfile->mi_valid = true; + pfile->mi_cmacro = 0; + + /* Generate the call back. */ + _cpp_do_file_change (pfile, LC_ENTER, file->path, 1, sysp); + + return true; +} + +/* Mark FILE to be included once only. */ +void +_cpp_mark_file_once_only (cpp_reader *pfile, _cpp_file *file) +{ + pfile->seen_once_only = true; + file->once_only = true; +} + +/* Return the directory from which searching for FNAME should start, + considering the directive TYPE and ANGLE_BRACKETS. If there is + nothing left in the path, returns NULL. */ +static struct cpp_dir * +search_path_head (cpp_reader *pfile, const char *fname, int angle_brackets, + enum include_type type) +{ + cpp_dir *dir; + _cpp_file *file; + + if (IS_ABSOLUTE_PATH (fname)) + return &pfile->no_search_path; + + /* pfile->buffer is NULL when processing an -include command-line flag. */ + file = pfile->buffer == NULL ? pfile->main_file : pfile->buffer->file; + + /* For #include_next, skip in the search path past the dir in which + the current file was found, but if it was found via an absolute + path use the normal search logic. */ + if (type == IT_INCLUDE_NEXT && file->dir + && file->dir != &pfile->no_search_path) + dir = file->dir->next; + else if (angle_brackets) + dir = pfile->bracket_include; + else if (type == IT_CMDLINE) + /* -include and -imacros use the #include "" chain with the + preprocessor's cwd prepended. */ + return make_cpp_dir (pfile, "./", false); + else if (pfile->quote_ignores_source_dir) + dir = pfile->quote_include; + else + return make_cpp_dir (pfile, dir_name_of_file (file), + pfile->buffer ? pfile->buffer->sysp : 0); + + if (dir == NULL) + cpp_error (pfile, CPP_DL_ERROR, + "no include path in which to search for %s", fname); + + return dir; +} + +/* Strip the basename from the file's path. It ends with a slash if + of nonzero length. Note that this procedure also works for + <stdin>, which is represented by the empty string. */ +static const char * +dir_name_of_file (_cpp_file *file) +{ + if (!file->dir_name) + { + size_t len = lbasename (file->path) - file->path; + char *dir_name = XNEWVEC (char, len + 1); + + memcpy (dir_name, file->path, len); + dir_name[len] = '\0'; + file->dir_name = dir_name; + } + + return file->dir_name; +} + +/* Handles #include-family directives (distinguished by TYPE), + including HEADER, and the command line -imacros and -include. + Returns true if a buffer was stacked. */ +bool +_cpp_stack_include (cpp_reader *pfile, const char *fname, int angle_brackets, + enum include_type type) +{ + struct cpp_dir *dir; + _cpp_file *file; + + dir = search_path_head (pfile, fname, angle_brackets, type); + if (!dir) + return false; + + file = _cpp_find_file (pfile, fname, dir, false, angle_brackets); + + /* Compensate for the increment in linemap_add that occurs in + _cpp_stack_file. In the case of a normal #include, we're + currently at the start of the line *following* the #include. A + separate source_location for this location makes no sense (until + we do the LC_LEAVE), and complicates LAST_SOURCE_LINE_LOCATION. + This does not apply if we found a PCH file (in which case + linemap_add is not called) or we were included from the + command-line. */ + if (file->pchname == NULL && file->err_no == 0 && type != IT_CMDLINE) + pfile->line_table->highest_location--; + + return _cpp_stack_file (pfile, file, type == IT_IMPORT); +} + +/* Could not open FILE. The complication is dependency output. */ +static void +open_file_failed (cpp_reader *pfile, _cpp_file *file, int angle_brackets) +{ + int sysp = pfile->line_table->highest_line > 1 && pfile->buffer ? pfile->buffer->sysp : 0; + bool print_dep = CPP_OPTION (pfile, deps.style) > (angle_brackets || !!sysp); + + errno = file->err_no; + if (print_dep && CPP_OPTION (pfile, deps.missing_files) && errno == ENOENT) + { + deps_add_dep (pfile->deps, file->name); + /* If the preprocessor output (other than dependency information) is + being used, we must also flag an error. */ + if (CPP_OPTION (pfile, deps.need_preprocessor_output)) + cpp_errno (pfile, CPP_DL_FATAL, file->path); + } + else + { + /* If we are not outputting dependencies, or if we are and dependencies + were requested for this file, or if preprocessor output is needed + in addition to dependency information, this is an error. + + Otherwise (outputting dependencies but not for this file, and not + using the preprocessor output), we can still produce correct output + so it's only a warning. */ + if (CPP_OPTION (pfile, deps.style) == DEPS_NONE + || print_dep + || CPP_OPTION (pfile, deps.need_preprocessor_output)) + cpp_errno (pfile, CPP_DL_FATAL, file->path); + else + cpp_errno (pfile, CPP_DL_WARNING, file->path); + } +} + +/* Search in the chain beginning at HEAD for a file whose search path + started at START_DIR != NULL. */ +static struct file_hash_entry * +search_cache (struct file_hash_entry *head, const cpp_dir *start_dir) +{ + while (head && head->start_dir != start_dir) + head = head->next; + + return head; +} + +/* Allocate a new _cpp_file structure. */ +static _cpp_file * +make_cpp_file (cpp_reader *pfile, cpp_dir *dir, const char *fname) +{ + _cpp_file *file; + + file = XCNEW (_cpp_file); + file->main_file = !pfile->buffer; + file->fd = -1; + file->dir = dir; + file->name = xstrdup (fname); + + return file; +} + +/* Release a _cpp_file structure. */ +static void +destroy_cpp_file (_cpp_file *file) +{ + if (file->buffer_start) + free ((void *) file->buffer_start); + free ((void *) file->name); + free (file); +} + +/* Release all the files allocated by this reader. */ +static void +destroy_all_cpp_files (cpp_reader *pfile) +{ + _cpp_file *iter = pfile->all_files; + while (iter) + { + _cpp_file *next = iter->next_file; + destroy_cpp_file (iter); + iter = next; + } +} + +/* A hash of directory names. The directory names are the path names + of files which contain a #include "", the included file name is + appended to this directories. + + To avoid duplicate entries we follow the convention that all + non-empty directory names should end in a '/'. DIR_NAME must be + stored in permanently allocated memory. */ +static cpp_dir * +make_cpp_dir (cpp_reader *pfile, const char *dir_name, int sysp) +{ + struct file_hash_entry *entry, **hash_slot; + cpp_dir *dir; + + hash_slot = (struct file_hash_entry **) + htab_find_slot_with_hash (pfile->dir_hash, dir_name, + htab_hash_string (dir_name), + INSERT); + + /* Have we already hashed this directory? */ + for (entry = *hash_slot; entry; entry = entry->next) + if (entry->start_dir == NULL) + return entry->u.dir; + + dir = XCNEW (cpp_dir); + dir->next = pfile->quote_include; + dir->name = (char *) dir_name; + dir->len = strlen (dir_name); + dir->sysp = sysp; + dir->construct = 0; + + /* Store this new result in the hash table. */ + entry = new_file_hash_entry (pfile); + entry->next = *hash_slot; + entry->start_dir = NULL; + entry->location = pfile->line_table->highest_location; + entry->u.dir = dir; + *hash_slot = entry; + + return dir; +} + +/* Create a new block of memory for file hash entries. */ +static void +allocate_file_hash_entries (cpp_reader *pfile) +{ + struct file_hash_entry_pool *pool = XNEW (struct file_hash_entry_pool); + pool->file_hash_entries_used = 0; + pool->next = pfile->file_hash_entries; + pfile->file_hash_entries = pool; +} + +/* Return a new file hash entry. */ +static struct file_hash_entry * +new_file_hash_entry (cpp_reader *pfile) +{ + unsigned int idx; + if (pfile->file_hash_entries->file_hash_entries_used == FILE_HASH_POOL_SIZE) + allocate_file_hash_entries (pfile); + + idx = pfile->file_hash_entries->file_hash_entries_used++; + return &pfile->file_hash_entries->pool[idx]; +} + +/* Free the file hash entry pools. */ +static void +free_file_hash_entries (cpp_reader *pfile) +{ + struct file_hash_entry_pool *iter = pfile->file_hash_entries; + while (iter) + { + struct file_hash_entry_pool *next = iter->next; + free (iter); + iter = next; + } +} + +/* Returns TRUE if a file FNAME has ever been successfully opened. + This routine is not intended to correctly handle filenames aliased + by links or redundant . or .. traversals etc. */ +bool +cpp_included (cpp_reader *pfile, const char *fname) +{ + struct file_hash_entry *entry; + + entry = (struct file_hash_entry *) + htab_find_with_hash (pfile->file_hash, fname, htab_hash_string (fname)); + + while (entry && (entry->start_dir == NULL || entry->u.file->err_no)) + entry = entry->next; + + return entry != NULL; +} + +/* Returns TRUE if a file FNAME has ever been successfully opened + before LOCATION. This routine is not intended to correctly handle + filenames aliased by links or redundant . or .. traversals etc. */ +bool +cpp_included_before (cpp_reader *pfile, const char *fname, + source_location location) +{ + struct file_hash_entry *entry; + + entry = (struct file_hash_entry *) + htab_find_with_hash (pfile->file_hash, fname, htab_hash_string (fname)); + + while (entry && (entry->start_dir == NULL || entry->u.file->err_no + || entry->location > location)) + entry = entry->next; + + return entry != NULL; +} + +/* Calculate the hash value of a file hash entry P. */ + +static hashval_t +file_hash_hash (const void *p) +{ + struct file_hash_entry *entry = (struct file_hash_entry *) p; + const char *hname; + if (entry->start_dir) + hname = entry->u.file->name; + else + hname = entry->u.dir->name; + + return htab_hash_string (hname); +} + +/* Compare a string Q against a file hash entry P. */ +static int +file_hash_eq (const void *p, const void *q) +{ + struct file_hash_entry *entry = (struct file_hash_entry *) p; + const char *fname = (const char *) q; + const char *hname; + + if (entry->start_dir) + hname = entry->u.file->name; + else + hname = entry->u.dir->name; + + return strcmp (hname, fname) == 0; +} + +/* Compare entries in the nonexistent file hash table. These are just + strings. */ +static int +nonexistent_file_hash_eq (const void *p, const void *q) +{ + return strcmp ((const char *) p, (const char *) q) == 0; +} + +/* Initialize everything in this source file. */ +void +_cpp_init_files (cpp_reader *pfile) +{ + pfile->file_hash = htab_create_alloc (127, file_hash_hash, file_hash_eq, + NULL, xcalloc, free); + pfile->dir_hash = htab_create_alloc (127, file_hash_hash, file_hash_eq, + NULL, xcalloc, free); + allocate_file_hash_entries (pfile); + pfile->nonexistent_file_hash = htab_create_alloc (127, htab_hash_string, + nonexistent_file_hash_eq, + NULL, xcalloc, free); + _obstack_begin (&pfile->nonexistent_file_ob, 0, 0, + (void *(*) (long)) xmalloc, + (void (*) (void *)) free); +} + +/* Finalize everything in this source file. */ +void +_cpp_cleanup_files (cpp_reader *pfile) +{ + htab_delete (pfile->file_hash); + htab_delete (pfile->dir_hash); + htab_delete (pfile->nonexistent_file_hash); + obstack_free (&pfile->nonexistent_file_ob, 0); + free_file_hash_entries (pfile); + destroy_all_cpp_files (pfile); +} + +/* Make the parser forget about files it has seen. This can be useful + for resetting the parser to start another run. */ +void +cpp_clear_file_cache (cpp_reader *pfile) +{ + _cpp_cleanup_files (pfile); + pfile->file_hash_entries = NULL; + pfile->all_files = NULL; + _cpp_init_files (pfile); +} + +/* Enter a file name in the hash for the sake of cpp_included. */ +void +_cpp_fake_include (cpp_reader *pfile, const char *fname) +{ + _cpp_find_file (pfile, fname, pfile->buffer->file->dir, true, 0); +} + +/* Not everyone who wants to set system-header-ness on a buffer can + see the details of a buffer. This is an exported interface because + fix-header needs it. */ +void +cpp_make_system_header (cpp_reader *pfile, int syshdr, int externc) +{ + int flags = 0; + const struct line_maps *line_table = pfile->line_table; + const struct line_map *map = &line_table->maps[line_table->used-1]; + + /* 1 = system header, 2 = system header to be treated as C. */ + if (syshdr) + flags = 1 + (externc != 0); + pfile->buffer->sysp = flags; + _cpp_do_file_change (pfile, LC_RENAME, map->to_file, + SOURCE_LINE (map, pfile->line_table->highest_line), flags); +} + +/* Allow the client to change the current file. Used by the front end + to achieve pseudo-file names like <built-in>. + If REASON is LC_LEAVE, then NEW_NAME must be NULL. */ +void +cpp_change_file (cpp_reader *pfile, enum lc_reason reason, + const char *new_name) +{ + _cpp_do_file_change (pfile, reason, new_name, 1, 0); +} + +struct report_missing_guard_data +{ + const char **paths; + size_t count; +}; + +/* Callback function for htab_traverse. */ +static int +report_missing_guard (void **slot, void *d) +{ + struct file_hash_entry *entry = (struct file_hash_entry *) *slot; + struct report_missing_guard_data *data + = (struct report_missing_guard_data *) d; + + /* Skip directories. */ + if (entry->start_dir != NULL) + { + _cpp_file *file = entry->u.file; + + /* We don't want MI guard advice for the main file. */ + if (!file->once_only && file->cmacro == NULL + && file->stack_count == 1 && !file->main_file) + { + if (data->paths == NULL) + { + data->paths = XCNEWVEC (const char *, data->count); + data->count = 0; + } + + data->paths[data->count++] = file->path; + } + } + + /* Keep traversing the hash table. */ + return 1; +} + +/* Comparison function for qsort. */ +static int +report_missing_guard_cmp (const void *p1, const void *p2) +{ + return strcmp (*(const char *const *) p1, *(const char *const *) p2); +} + +/* Report on all files that might benefit from a multiple include guard. + Triggered by -H. */ +void +_cpp_report_missing_guards (cpp_reader *pfile) +{ + struct report_missing_guard_data data; + + data.paths = NULL; + data.count = htab_elements (pfile->file_hash); + htab_traverse (pfile->file_hash, report_missing_guard, &data); + + if (data.paths != NULL) + { + size_t i; + + /* Sort the paths to avoid outputting them in hash table + order. */ + qsort (data.paths, data.count, sizeof (const char *), + report_missing_guard_cmp); + fputs (_("Multiple include guards may be useful for:\n"), + stderr); + for (i = 0; i < data.count; i++) + { + fputs (data.paths[i], stderr); + putc ('\n', stderr); + } + free (data.paths); + } +} + +/* Locate HEADER, and determine whether it is newer than the current + file. If it cannot be located or dated, return -1, if it is + newer, return 1, otherwise 0. */ +int +_cpp_compare_file_date (cpp_reader *pfile, const char *fname, + int angle_brackets) +{ + _cpp_file *file; + struct cpp_dir *dir; + + dir = search_path_head (pfile, fname, angle_brackets, IT_INCLUDE); + if (!dir) + return -1; + + file = _cpp_find_file (pfile, fname, dir, false, angle_brackets); + if (file->err_no) + return -1; + + if (file->fd != -1) + { + close (file->fd); + file->fd = -1; + } + + return file->st.st_mtime > pfile->buffer->file->st.st_mtime; +} + +/* Pushes the given file onto the buffer stack. Returns nonzero if + successful. */ +bool +cpp_push_include (cpp_reader *pfile, const char *fname) +{ + return _cpp_stack_include (pfile, fname, false, IT_CMDLINE); +} + +/* Do appropriate cleanup when a file INC's buffer is popped off the + input stack. */ +void +_cpp_pop_file_buffer (cpp_reader *pfile, _cpp_file *file) +{ + /* Record the inclusion-preventing macro, which could be NULL + meaning no controlling macro. */ + if (pfile->mi_valid && file->cmacro == NULL) + file->cmacro = pfile->mi_cmacro; + + /* Invalidate control macros in the #including file. */ + pfile->mi_valid = false; + + if (file->buffer_start) + { + free ((void *) file->buffer_start); + file->buffer_start = NULL; + file->buffer = NULL; + file->buffer_valid = false; + } +} + +/* Inteface to file statistics record in _cpp_file structure. */ +struct stat * +_cpp_get_file_stat (_cpp_file *file) +{ + return &file->st; +} + +/* Set the include chain for "" to QUOTE, for <> to BRACKET. If + QUOTE_IGNORES_SOURCE_DIR, then "" includes do not look in the + directory of the including file. + + If BRACKET does not lie in the QUOTE chain, it is set to QUOTE. */ +void +cpp_set_include_chains (cpp_reader *pfile, cpp_dir *quote, cpp_dir *bracket, + int quote_ignores_source_dir) +{ + pfile->quote_include = quote; + pfile->bracket_include = quote; + pfile->quote_ignores_source_dir = quote_ignores_source_dir; + + for (; quote; quote = quote->next) + { + quote->name_map = NULL; + quote->len = strlen (quote->name); + if (quote == bracket) + pfile->bracket_include = bracket; + } +} + +/* Append the file name to the directory to create the path, but don't + turn / into // or // into ///; // may be a namespace escape. */ +static char * +append_file_to_dir (const char *fname, cpp_dir *dir) +{ + size_t dlen, flen; + char *path; + + dlen = dir->len; + flen = strlen (fname); + path = XNEWVEC (char, dlen + 1 + flen + 1); + memcpy (path, dir->name, dlen); + if (dlen && path[dlen - 1] != '/') + path[dlen++] = '/'; + memcpy (&path[dlen], fname, flen + 1); + + return path; +} + +/* Read a space delimited string of unlimited length from a stdio + file F. */ +static char * +read_filename_string (int ch, FILE *f) +{ + char *alloc, *set; + int len; + + len = 20; + set = alloc = XNEWVEC (char, len + 1); + if (! is_space (ch)) + { + *set++ = ch; + while ((ch = getc (f)) != EOF && ! is_space (ch)) + { + if (set - alloc == len) + { + len *= 2; + alloc = XRESIZEVEC (char, alloc, len + 1); + set = alloc + len / 2; + } + *set++ = ch; + } + } + *set = '\0'; + ungetc (ch, f); + return alloc; +} + +/* Read the file name map file for DIR. */ +static void +read_name_map (cpp_dir *dir) +{ + static const char FILE_NAME_MAP_FILE[] = "header.gcc"; + char *name; + FILE *f; + size_t len, count = 0, room = 9; + + len = dir->len; + name = (char *) alloca (len + sizeof (FILE_NAME_MAP_FILE) + 1); + memcpy (name, dir->name, len); + if (len && name[len - 1] != '/') + name[len++] = '/'; + strcpy (name + len, FILE_NAME_MAP_FILE); + f = fopen (name, "r"); + + dir->name_map = XNEWVEC (const char *, room); + + /* Silently return NULL if we cannot open. */ + if (f) + { + int ch; + + while ((ch = getc (f)) != EOF) + { + char *to; + + if (is_space (ch)) + continue; + + if (count + 2 > room) + { + room += 8; + dir->name_map = XRESIZEVEC (const char *, dir->name_map, room); + } + + dir->name_map[count] = read_filename_string (ch, f); + while ((ch = getc (f)) != EOF && is_hspace (ch)) + ; + + to = read_filename_string (ch, f); + if (IS_ABSOLUTE_PATH (to)) + dir->name_map[count + 1] = to; + else + { + dir->name_map[count + 1] = append_file_to_dir (to, dir); + free (to); + } + + count += 2; + while ((ch = getc (f)) != '\n') + if (ch == EOF) + break; + } + + fclose (f); + } + + /* Terminate the list of maps. */ + dir->name_map[count] = NULL; +} + +/* Remap a FILE's name based on the file_name_map, if any, for + FILE->dir. If the file name has any directory separators, + recursively check those directories too. */ +static char * +remap_filename (cpp_reader *pfile, _cpp_file *file) +{ + const char *fname, *p; + char *new_dir; + cpp_dir *dir; + size_t index, len; + + dir = file->dir; + fname = file->name; + + for (;;) + { + if (!dir->name_map) + read_name_map (dir); + + for (index = 0; dir->name_map[index]; index += 2) + if (!strcmp (dir->name_map[index], fname)) + return xstrdup (dir->name_map[index + 1]); + + p = strchr (fname, '/'); + if (!p || p == fname) + return NULL; + + len = dir->len + (p - fname + 1); + new_dir = XNEWVEC (char, len + 1); + memcpy (new_dir, dir->name, dir->len); + memcpy (new_dir + dir->len, fname, p - fname + 1); + new_dir[len] = '\0'; + + dir = make_cpp_dir (pfile, new_dir, dir->sysp); + fname = p + 1; + } +} + +/* Returns true if PCHNAME is a valid PCH file for FILE. */ +static bool +validate_pch (cpp_reader *pfile, _cpp_file *file, const char *pchname) +{ + const char *saved_path = file->path; + bool valid = false; + + file->path = pchname; + if (open_file (file)) + { + valid = 1 & pfile->cb.valid_pch (pfile, pchname, file->fd); + + if (!valid) + { + close (file->fd); + file->fd = -1; + } + + if (CPP_OPTION (pfile, print_include_names)) + { + unsigned int i; + for (i = 1; i < pfile->line_table->depth; i++) + putc ('.', stderr); + fprintf (stderr, "%c %s\n", + valid ? '!' : 'x', pchname); + } + } + + file->path = saved_path; + return valid; +} + +/* Get the path associated with the _cpp_file F. The path includes + the base name from the include directive and the directory it was + found in via the search path. */ + +const char * +cpp_get_path (struct _cpp_file *f) +{ + return f->path; +} + +/* Get the directory associated with the _cpp_file F. */ + +cpp_dir * +cpp_get_dir (struct _cpp_file *f) +{ + return f->dir; +} + +/* Get the cpp_buffer currently associated with the cpp_reader + PFILE. */ + +cpp_buffer * +cpp_get_buffer (cpp_reader *pfile) +{ + return pfile->buffer; +} + +/* Get the _cpp_file associated with the cpp_buffer B. */ + +_cpp_file * +cpp_get_file (cpp_buffer *b) +{ + return b->file; +} + +/* Get the previous cpp_buffer given a cpp_buffer B. The previous + buffer is the buffer that included the given buffer. */ + +cpp_buffer * +cpp_get_prev (cpp_buffer *b) +{ + return b->prev; +} + +/* This data structure holds the list of header files that were seen + while the PCH was being built. The 'entries' field is kept sorted + in memcmp() order; yes, this means that on little-endian systems, + it's sorted initially by the least-significant byte of 'size', but + that's OK. The code does rely on having entries with the same size + next to each other. */ + +struct pchf_entry { + /* The size of this file. This is used to save running a MD5 checksum + if the sizes don't match. */ + off_t size; + /* The MD5 checksum of this file. */ + unsigned char sum[16]; + /* Is this file to be included only once? */ + bool once_only; +}; + +struct pchf_data { + /* Number of pchf_entry structures. */ + size_t count; + + /* Are there any values with once_only set? + This is used as an optimisation, it means we don't have to search + the structure if we're processing a regular #include. */ + bool have_once_only; + + struct pchf_entry entries[1]; +}; + +static struct pchf_data *pchf; + +/* A qsort ordering function for pchf_entry structures. */ + +static int +pchf_save_compare (const void *e1, const void *e2) +{ + return memcmp (e1, e2, sizeof (struct pchf_entry)); +} + +/* Create and write to F a pchf_data structure. */ + +bool +_cpp_save_file_entries (cpp_reader *pfile, FILE *fp) +{ + size_t count = 0; + struct pchf_data *result; + size_t result_size; + _cpp_file *f; + + for (f = pfile->all_files; f; f = f->next_file) + ++count; + + result_size = (sizeof (struct pchf_data) + + sizeof (struct pchf_entry) * (count - 1)); + result = XCNEWVAR (struct pchf_data, result_size); + + result->count = 0; + result->have_once_only = false; + + for (f = pfile->all_files; f; f = f->next_file) + { + size_t count; + + /* This should probably never happen, since if a read error occurred + the PCH file shouldn't be written... */ + if (f->dont_read || f->err_no) + continue; + + if (f->stack_count == 0) + continue; + + count = result->count++; + + result->entries[count].once_only = f->once_only; + /* |= is avoided in the next line because of an HP C compiler bug */ + result->have_once_only = result->have_once_only | f->once_only; + if (f->buffer_valid) + md5_buffer ((const char *)f->buffer, + f->st.st_size, result->entries[count].sum); + else + { + FILE *ff; + int oldfd = f->fd; + + if (!open_file (f)) + { + open_file_failed (pfile, f, 0); + return false; + } + ff = fdopen (f->fd, "rb"); + md5_stream (ff, result->entries[count].sum); + fclose (ff); + f->fd = oldfd; + } + result->entries[count].size = f->st.st_size; + } + + result_size = (sizeof (struct pchf_data) + + sizeof (struct pchf_entry) * (result->count - 1)); + + qsort (result->entries, result->count, sizeof (struct pchf_entry), + pchf_save_compare); + + return fwrite (result, result_size, 1, fp) == 1; +} + +/* Read the pchf_data structure from F. */ + +bool +_cpp_read_file_entries (cpp_reader *pfile ATTRIBUTE_UNUSED, FILE *f) +{ + struct pchf_data d; + + if (fread (&d, sizeof (struct pchf_data) - sizeof (struct pchf_entry), 1, f) + != 1) + return false; + + pchf = XNEWVAR (struct pchf_data, sizeof (struct pchf_data) + + sizeof (struct pchf_entry) * (d.count - 1)); + memcpy (pchf, &d, sizeof (struct pchf_data) - sizeof (struct pchf_entry)); + if (fread (pchf->entries, sizeof (struct pchf_entry), d.count, f) + != d.count) + return false; + return true; +} + +/* The parameters for pchf_compare. */ + +struct pchf_compare_data +{ + /* The size of the file we're looking for. */ + off_t size; + + /* The MD5 checksum of the file, if it's been computed. */ + unsigned char sum[16]; + + /* Is SUM valid? */ + bool sum_computed; + + /* Do we need to worry about entries that don't have ONCE_ONLY set? */ + bool check_included; + + /* The file that we're searching for. */ + _cpp_file *f; +}; + +/* bsearch comparison function; look for D_P in E_P. */ + +static int +pchf_compare (const void *d_p, const void *e_p) +{ + const struct pchf_entry *e = (const struct pchf_entry *)e_p; + struct pchf_compare_data *d = (struct pchf_compare_data *)d_p; + int result; + + result = memcmp (&d->size, &e->size, sizeof (off_t)); + if (result != 0) + return result; + + if (! d->sum_computed) + { + _cpp_file *const f = d->f; + + md5_buffer ((const char *)f->buffer, f->st.st_size, d->sum); + d->sum_computed = true; + } + + result = memcmp (d->sum, e->sum, 16); + if (result != 0) + return result; + + if (d->check_included || e->once_only) + return 0; + else + return 1; +} + +/* Check that F is not in a list read from a PCH file (if any). + Assumes that f->buffer_valid is true. Return TRUE if the file + should not be read. */ + +static bool +check_file_against_entries (cpp_reader *pfile ATTRIBUTE_UNUSED, + _cpp_file *f, + bool check_included) +{ + struct pchf_compare_data d; + + if (pchf == NULL + || (! check_included && ! pchf->have_once_only)) + return false; + + d.size = f->st.st_size; + d.sum_computed = false; + d.f = f; + d.check_included = check_included; + return bsearch (&d, pchf->entries, pchf->count, sizeof (struct pchf_entry), + pchf_compare) != NULL; +} |