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[/] [openrisc/] [tags/] [gnu-src/] [gcc-4.5.1/] [gcc-4.5.1-or32-1.0rc4/] [gcc/] [fortran/] [scanner.c] - Rev 519
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/* Character scanner. Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc. Contributed by Andy Vaught This file is part of GCC. 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 3, 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 COPYING3. If not see <http://www.gnu.org/licenses/>. */ /* Set of subroutines to (ultimately) return the next character to the various matching subroutines. This file's job is to read files and build up lines that are parsed by the parser. This means that we handle continuation lines and "include" lines. The first thing the scanner does is to load an entire file into memory. We load the entire file into memory for a couple reasons. The first is that we want to be able to deal with nonseekable input (pipes, stdin) and there is a lot of backing up involved during parsing. The second is that we want to be able to print the locus of errors, and an error on line 999999 could conflict with something on line one. Given nonseekable input, we've got to store the whole thing. One thing that helps are the column truncation limits that give us an upper bound on the size of individual lines. We don't store the truncated stuff. From the scanner's viewpoint, the higher level subroutines ask for new characters and do a lot of jumping backwards. */ #include "config.h" #include "system.h" #include "gfortran.h" #include "toplev.h" #include "debug.h" #include "flags.h" #include "cpp.h" /* Structure for holding module and include file search path. */ typedef struct gfc_directorylist { char *path; bool use_for_modules; struct gfc_directorylist *next; } gfc_directorylist; /* List of include file search directories. */ static gfc_directorylist *include_dirs, *intrinsic_modules_dirs; static gfc_file *file_head, *current_file; static int continue_flag, end_flag, openmp_flag, gcc_attribute_flag; static int continue_count, continue_line; static locus openmp_locus; static locus gcc_attribute_locus; gfc_source_form gfc_current_form; static gfc_linebuf *line_head, *line_tail; locus gfc_current_locus; const char *gfc_source_file; static FILE *gfc_src_file; static gfc_char_t *gfc_src_preprocessor_lines[2]; extern int pedantic; static struct gfc_file_change { const char *filename; gfc_linebuf *lb; int line; } *file_changes; size_t file_changes_cur, file_changes_count; size_t file_changes_allocated; /* Functions dealing with our wide characters (gfc_char_t) and sequences of such characters. */ int gfc_wide_fits_in_byte (gfc_char_t c) { return (c <= UCHAR_MAX); } static inline int wide_is_ascii (gfc_char_t c) { return (gfc_wide_fits_in_byte (c) && ((unsigned char) c & ~0x7f) == 0); } int gfc_wide_is_printable (gfc_char_t c) { return (gfc_wide_fits_in_byte (c) && ISPRINT ((unsigned char) c)); } gfc_char_t gfc_wide_tolower (gfc_char_t c) { return (wide_is_ascii (c) ? (gfc_char_t) TOLOWER((unsigned char) c) : c); } gfc_char_t gfc_wide_toupper (gfc_char_t c) { return (wide_is_ascii (c) ? (gfc_char_t) TOUPPER((unsigned char) c) : c); } int gfc_wide_is_digit (gfc_char_t c) { return (c >= '0' && c <= '9'); } static inline int wide_atoi (gfc_char_t *c) { #define MAX_DIGITS 20 char buf[MAX_DIGITS+1]; int i = 0; while (gfc_wide_is_digit(*c) && i < MAX_DIGITS) buf[i++] = *c++; buf[i] = '\0'; return atoi (buf); } size_t gfc_wide_strlen (const gfc_char_t *str) { size_t i; for (i = 0; str[i]; i++) ; return i; } gfc_char_t * gfc_wide_memset (gfc_char_t *b, gfc_char_t c, size_t len) { size_t i; for (i = 0; i < len; i++) b[i] = c; return b; } static gfc_char_t * wide_strcpy (gfc_char_t *dest, const gfc_char_t *src) { gfc_char_t *d; for (d = dest; (*d = *src) != '\0'; ++src, ++d) ; return dest; } static gfc_char_t * wide_strchr (const gfc_char_t *s, gfc_char_t c) { do { if (*s == c) { return CONST_CAST(gfc_char_t *, s); } } while (*s++); return 0; } char * gfc_widechar_to_char (const gfc_char_t *s, int length) { size_t len, i; char *res; if (s == NULL) return NULL; /* Passing a negative length is used to indicate that length should be calculated using gfc_wide_strlen(). */ len = (length >= 0 ? (size_t) length : gfc_wide_strlen (s)); res = XNEWVEC (char, len + 1); for (i = 0; i < len; i++) { gcc_assert (gfc_wide_fits_in_byte (s[i])); res[i] = (unsigned char) s[i]; } res[len] = '\0'; return res; } gfc_char_t * gfc_char_to_widechar (const char *s) { size_t len, i; gfc_char_t *res; if (s == NULL) return NULL; len = strlen (s); res = gfc_get_wide_string (len + 1); for (i = 0; i < len; i++) res[i] = (unsigned char) s[i]; res[len] = '\0'; return res; } static int wide_strncmp (const gfc_char_t *s1, const char *s2, size_t n) { gfc_char_t c1, c2; while (n-- > 0) { c1 = *s1++; c2 = *s2++; if (c1 != c2) return (c1 > c2 ? 1 : -1); if (c1 == '\0') return 0; } return 0; } int gfc_wide_strncasecmp (const gfc_char_t *s1, const char *s2, size_t n) { gfc_char_t c1, c2; while (n-- > 0) { c1 = gfc_wide_tolower (*s1++); c2 = TOLOWER (*s2++); if (c1 != c2) return (c1 > c2 ? 1 : -1); if (c1 == '\0') return 0; } return 0; } /* Main scanner initialization. */ void gfc_scanner_init_1 (void) { file_head = NULL; line_head = NULL; line_tail = NULL; continue_count = 0; continue_line = 0; end_flag = 0; } /* Main scanner destructor. */ void gfc_scanner_done_1 (void) { gfc_linebuf *lb; gfc_file *f; while(line_head != NULL) { lb = line_head->next; gfc_free(line_head); line_head = lb; } while(file_head != NULL) { f = file_head->next; gfc_free(file_head->filename); gfc_free(file_head); file_head = f; } } /* Adds path to the list pointed to by list. */ static void add_path_to_list (gfc_directorylist **list, const char *path, bool use_for_modules, bool head) { gfc_directorylist *dir; const char *p; p = path; while (*p == ' ' || *p == '\t') /* someone might do "-I include" */ if (*p++ == '\0') return; if (head || *list == NULL) { dir = XCNEW (gfc_directorylist); if (!head) *list = dir; } else { dir = *list; while (dir->next) dir = dir->next; dir->next = XCNEW (gfc_directorylist); dir = dir->next; } dir->next = head ? *list : NULL; if (head) *list = dir; dir->use_for_modules = use_for_modules; dir->path = XCNEWVEC (char, strlen (p) + 2); strcpy (dir->path, p); strcat (dir->path, "/"); /* make '/' last character */ } void gfc_add_include_path (const char *path, bool use_for_modules, bool file_dir) { add_path_to_list (&include_dirs, path, use_for_modules, file_dir); /* For '#include "..."' these directories are automatically searched. */ if (!file_dir) gfc_cpp_add_include_path (xstrdup(path), true); } void gfc_add_intrinsic_modules_path (const char *path) { add_path_to_list (&intrinsic_modules_dirs, path, true, false); } /* Release resources allocated for options. */ void gfc_release_include_path (void) { gfc_directorylist *p; while (include_dirs != NULL) { p = include_dirs; include_dirs = include_dirs->next; gfc_free (p->path); gfc_free (p); } while (intrinsic_modules_dirs != NULL) { p = intrinsic_modules_dirs; intrinsic_modules_dirs = intrinsic_modules_dirs->next; gfc_free (p->path); gfc_free (p); } gfc_free (gfc_option.module_dir); } static FILE * open_included_file (const char *name, gfc_directorylist *list, bool module, bool system) { char *fullname; gfc_directorylist *p; FILE *f; for (p = list; p; p = p->next) { if (module && !p->use_for_modules) continue; fullname = (char *) alloca(strlen (p->path) + strlen (name) + 1); strcpy (fullname, p->path); strcat (fullname, name); f = gfc_open_file (fullname); if (f != NULL) { if (gfc_cpp_makedep ()) gfc_cpp_add_dep (fullname, system); return f; } } return NULL; } /* Opens file for reading, searching through the include directories given if necessary. If the include_cwd argument is true, we try to open the file in the current directory first. */ FILE * gfc_open_included_file (const char *name, bool include_cwd, bool module) { FILE *f = NULL; if (IS_ABSOLUTE_PATH (name) || include_cwd) { f = gfc_open_file (name); if (f && gfc_cpp_makedep ()) gfc_cpp_add_dep (name, false); } if (!f) f = open_included_file (name, include_dirs, module, false); return f; } FILE * gfc_open_intrinsic_module (const char *name) { FILE *f = NULL; if (IS_ABSOLUTE_PATH (name)) { f = gfc_open_file (name); if (f && gfc_cpp_makedep ()) gfc_cpp_add_dep (name, true); } if (!f) f = open_included_file (name, intrinsic_modules_dirs, true, true); return f; } /* Test to see if we're at the end of the main source file. */ int gfc_at_end (void) { return end_flag; } /* Test to see if we're at the end of the current file. */ int gfc_at_eof (void) { if (gfc_at_end ()) return 1; if (line_head == NULL) return 1; /* Null file */ if (gfc_current_locus.lb == NULL) return 1; return 0; } /* Test to see if we're at the beginning of a new line. */ int gfc_at_bol (void) { if (gfc_at_eof ()) return 1; return (gfc_current_locus.nextc == gfc_current_locus.lb->line); } /* Test to see if we're at the end of a line. */ int gfc_at_eol (void) { if (gfc_at_eof ()) return 1; return (*gfc_current_locus.nextc == '\0'); } static void add_file_change (const char *filename, int line) { if (file_changes_count == file_changes_allocated) { if (file_changes_allocated) file_changes_allocated *= 2; else file_changes_allocated = 16; file_changes = XRESIZEVEC (struct gfc_file_change, file_changes, file_changes_allocated); } file_changes[file_changes_count].filename = filename; file_changes[file_changes_count].lb = NULL; file_changes[file_changes_count++].line = line; } static void report_file_change (gfc_linebuf *lb) { size_t c = file_changes_cur; while (c < file_changes_count && file_changes[c].lb == lb) { if (file_changes[c].filename) (*debug_hooks->start_source_file) (file_changes[c].line, file_changes[c].filename); else (*debug_hooks->end_source_file) (file_changes[c].line); ++c; } file_changes_cur = c; } void gfc_start_source_files (void) { /* If the debugger wants the name of the main source file, we give it. */ if (debug_hooks->start_end_main_source_file) (*debug_hooks->start_source_file) (0, gfc_source_file); file_changes_cur = 0; report_file_change (gfc_current_locus.lb); } void gfc_end_source_files (void) { report_file_change (NULL); if (debug_hooks->start_end_main_source_file) (*debug_hooks->end_source_file) (0); } /* Advance the current line pointer to the next line. */ void gfc_advance_line (void) { if (gfc_at_end ()) return; if (gfc_current_locus.lb == NULL) { end_flag = 1; return; } if (gfc_current_locus.lb->next && !gfc_current_locus.lb->next->dbg_emitted) { report_file_change (gfc_current_locus.lb->next); gfc_current_locus.lb->next->dbg_emitted = true; } gfc_current_locus.lb = gfc_current_locus.lb->next; if (gfc_current_locus.lb != NULL) gfc_current_locus.nextc = gfc_current_locus.lb->line; else { gfc_current_locus.nextc = NULL; end_flag = 1; } } /* Get the next character from the input, advancing gfc_current_file's locus. When we hit the end of the line or the end of the file, we start returning a '\n' in order to complete the current statement. No Fortran line conventions are implemented here. Requiring explicit advances to the next line prevents the parse pointer from being on the wrong line if the current statement ends prematurely. */ static gfc_char_t next_char (void) { gfc_char_t c; if (gfc_current_locus.nextc == NULL) return '\n'; c = *gfc_current_locus.nextc++; if (c == '\0') { gfc_current_locus.nextc--; /* Remain on this line. */ c = '\n'; } return c; } /* Skip a comment. When we come here the parse pointer is positioned immediately after the comment character. If we ever implement compiler directives within comments, here is where we parse the directive. */ static void skip_comment_line (void) { gfc_char_t c; do { c = next_char (); } while (c != '\n'); gfc_advance_line (); } int gfc_define_undef_line (void) { char *tmp; /* All lines beginning with '#' are either #define or #undef. */ if (debug_info_level != DINFO_LEVEL_VERBOSE || gfc_peek_ascii_char () != '#') return 0; if (wide_strncmp (gfc_current_locus.nextc, "#define ", 8) == 0) { tmp = gfc_widechar_to_char (&gfc_current_locus.nextc[8], -1); (*debug_hooks->define) (gfc_linebuf_linenum (gfc_current_locus.lb), tmp); gfc_free (tmp); } if (wide_strncmp (gfc_current_locus.nextc, "#undef ", 7) == 0) { tmp = gfc_widechar_to_char (&gfc_current_locus.nextc[7], -1); (*debug_hooks->undef) (gfc_linebuf_linenum (gfc_current_locus.lb), tmp); gfc_free (tmp); } /* Skip the rest of the line. */ skip_comment_line (); return 1; } /* Return true if GCC$ was matched. */ static bool skip_gcc_attribute (locus start) { bool r = false; char c; locus old_loc = gfc_current_locus; if ((c = next_char ()) == 'g' || c == 'G') if ((c = next_char ()) == 'c' || c == 'C') if ((c = next_char ()) == 'c' || c == 'C') if ((c = next_char ()) == '$') r = true; if (r == false) gfc_current_locus = old_loc; else { gcc_attribute_flag = 1; gcc_attribute_locus = old_loc; gfc_current_locus = start; } return r; } /* Comment lines are null lines, lines containing only blanks or lines on which the first nonblank line is a '!'. Return true if !$ openmp conditional compilation sentinel was seen. */ static bool skip_free_comments (void) { locus start; gfc_char_t c; int at_bol; for (;;) { at_bol = gfc_at_bol (); start = gfc_current_locus; if (gfc_at_eof ()) break; do c = next_char (); while (gfc_is_whitespace (c)); if (c == '\n') { gfc_advance_line (); continue; } if (c == '!') { /* Keep the !GCC$ line. */ if (at_bol && skip_gcc_attribute (start)) return false; /* If -fopenmp, we need to handle here 2 things: 1) don't treat !$omp as comments, but directives 2) handle OpenMP conditional compilation, where !$ should be treated as 2 spaces (for initial lines only if followed by space). */ if (gfc_option.flag_openmp && at_bol) { locus old_loc = gfc_current_locus; if (next_char () == '$') { c = next_char (); if (c == 'o' || c == 'O') { if (((c = next_char ()) == 'm' || c == 'M') && ((c = next_char ()) == 'p' || c == 'P')) { if ((c = next_char ()) == ' ' || c == '\t' || continue_flag) { while (gfc_is_whitespace (c)) c = next_char (); if (c != '\n' && c != '!') { openmp_flag = 1; openmp_locus = old_loc; gfc_current_locus = start; return false; } } else gfc_warning_now ("!$OMP at %C starts a commented " "line as it neither is followed " "by a space nor is a " "continuation line"); } gfc_current_locus = old_loc; next_char (); c = next_char (); } if (continue_flag || c == ' ' || c == '\t') { gfc_current_locus = old_loc; next_char (); openmp_flag = 0; return true; } } gfc_current_locus = old_loc; } skip_comment_line (); continue; } break; } if (openmp_flag && at_bol) openmp_flag = 0; gcc_attribute_flag = 0; gfc_current_locus = start; return false; } /* Skip comment lines in fixed source mode. We have the same rules as in skip_free_comment(), except that we can have a 'c', 'C' or '*' in column 1, and a '!' cannot be in column 6. Also, we deal with lines with 'd' or 'D' in column 1, if the user requested this. */ static void skip_fixed_comments (void) { locus start; int col; gfc_char_t c; if (! gfc_at_bol ()) { start = gfc_current_locus; if (! gfc_at_eof ()) { do c = next_char (); while (gfc_is_whitespace (c)); if (c == '\n') gfc_advance_line (); else if (c == '!') skip_comment_line (); } if (! gfc_at_bol ()) { gfc_current_locus = start; return; } } for (;;) { start = gfc_current_locus; if (gfc_at_eof ()) break; c = next_char (); if (c == '\n') { gfc_advance_line (); continue; } if (c == '!' || c == 'c' || c == 'C' || c == '*') { if (skip_gcc_attribute (start)) { /* Canonicalize to *$omp. */ *start.nextc = '*'; return; } /* If -fopenmp, we need to handle here 2 things: 1) don't treat !$omp|c$omp|*$omp as comments, but directives 2) handle OpenMP conditional compilation, where !$|c$|*$ should be treated as 2 spaces if the characters in columns 3 to 6 are valid fixed form label columns characters. */ if (gfc_current_locus.lb != NULL && continue_line < gfc_linebuf_linenum (gfc_current_locus.lb)) continue_line = gfc_linebuf_linenum (gfc_current_locus.lb); if (gfc_option.flag_openmp) { if (next_char () == '$') { c = next_char (); if (c == 'o' || c == 'O') { if (((c = next_char ()) == 'm' || c == 'M') && ((c = next_char ()) == 'p' || c == 'P')) { c = next_char (); if (c != '\n' && ((openmp_flag && continue_flag) || c == ' ' || c == '\t' || c == '0')) { do c = next_char (); while (gfc_is_whitespace (c)); if (c != '\n' && c != '!') { /* Canonicalize to *$omp. */ *start.nextc = '*'; openmp_flag = 1; gfc_current_locus = start; return; } } } } else { int digit_seen = 0; for (col = 3; col < 6; col++, c = next_char ()) if (c == ' ') continue; else if (c == '\t') { col = 6; break; } else if (c < '0' || c > '9') break; else digit_seen = 1; if (col == 6 && c != '\n' && ((continue_flag && !digit_seen) || c == ' ' || c == '\t' || c == '0')) { gfc_current_locus = start; start.nextc[0] = ' '; start.nextc[1] = ' '; continue; } } } gfc_current_locus = start; } skip_comment_line (); continue; } if (gfc_option.flag_d_lines != -1 && (c == 'd' || c == 'D')) { if (gfc_option.flag_d_lines == 0) { skip_comment_line (); continue; } else *start.nextc = c = ' '; } col = 1; while (gfc_is_whitespace (c)) { c = next_char (); col++; } if (c == '\n') { gfc_advance_line (); continue; } if (col != 6 && c == '!') { if (gfc_current_locus.lb != NULL && continue_line < gfc_linebuf_linenum (gfc_current_locus.lb)) continue_line = gfc_linebuf_linenum (gfc_current_locus.lb); skip_comment_line (); continue; } break; } openmp_flag = 0; gcc_attribute_flag = 0; gfc_current_locus = start; } /* Skips the current line if it is a comment. */ void gfc_skip_comments (void) { if (gfc_current_form == FORM_FREE) skip_free_comments (); else skip_fixed_comments (); } /* Get the next character from the input, taking continuation lines and end-of-line comments into account. This implies that comment lines between continued lines must be eaten here. For higher-level subroutines, this flattens continued lines into a single logical line. The in_string flag denotes whether we're inside a character context or not. */ gfc_char_t gfc_next_char_literal (int in_string) { locus old_loc; int i, prev_openmp_flag; gfc_char_t c; continue_flag = 0; restart: c = next_char (); if (gfc_at_end ()) { continue_count = 0; return c; } if (gfc_current_form == FORM_FREE) { bool openmp_cond_flag; if (!in_string && c == '!') { if (gcc_attribute_flag && memcmp (&gfc_current_locus, &gcc_attribute_locus, sizeof (gfc_current_locus)) == 0) goto done; if (openmp_flag && memcmp (&gfc_current_locus, &openmp_locus, sizeof (gfc_current_locus)) == 0) goto done; /* This line can't be continued */ do { c = next_char (); } while (c != '\n'); /* Avoid truncation warnings for comment ending lines. */ gfc_current_locus.lb->truncated = 0; goto done; } if (c != '&') goto done; /* If the next nonblank character is a ! or \n, we've got a continuation line. */ old_loc = gfc_current_locus; c = next_char (); while (gfc_is_whitespace (c)) c = next_char (); /* Character constants to be continued cannot have commentary after the '&'. */ if (in_string && c != '\n') { gfc_current_locus = old_loc; c = '&'; goto done; } if (c != '!' && c != '\n') { gfc_current_locus = old_loc; c = '&'; goto done; } prev_openmp_flag = openmp_flag; continue_flag = 1; if (c == '!') skip_comment_line (); else gfc_advance_line (); if (gfc_at_eof()) goto not_continuation; /* We've got a continuation line. If we are on the very next line after the last continuation, increment the continuation line count and check whether the limit has been exceeded. */ if (gfc_linebuf_linenum (gfc_current_locus.lb) == continue_line + 1) { if (++continue_count == gfc_option.max_continue_free) { if (gfc_notification_std (GFC_STD_GNU) || pedantic) gfc_warning ("Limit of %d continuations exceeded in " "statement at %C", gfc_option.max_continue_free); } } /* Check to see if the continuation line was truncated. */ if (gfc_option.warn_line_truncation && gfc_current_locus.lb != NULL && gfc_current_locus.lb->truncated) { int maxlen = gfc_option.free_line_length; gfc_current_locus.lb->truncated = 0; gfc_current_locus.nextc += maxlen; gfc_warning_now ("Line truncated at %L", &gfc_current_locus); gfc_current_locus.nextc -= maxlen; } /* Now find where it continues. First eat any comment lines. */ openmp_cond_flag = skip_free_comments (); if (gfc_current_locus.lb != NULL && continue_line < gfc_linebuf_linenum (gfc_current_locus.lb)) continue_line = gfc_linebuf_linenum (gfc_current_locus.lb); if (prev_openmp_flag != openmp_flag) { gfc_current_locus = old_loc; openmp_flag = prev_openmp_flag; c = '&'; goto done; } /* Now that we have a non-comment line, probe ahead for the first non-whitespace character. If it is another '&', then reading starts at the next character, otherwise we must back up to where the whitespace started and resume from there. */ old_loc = gfc_current_locus; c = next_char (); while (gfc_is_whitespace (c)) c = next_char (); if (openmp_flag) { for (i = 0; i < 5; i++, c = next_char ()) { gcc_assert (gfc_wide_tolower (c) == (unsigned char) "!$omp"[i]); if (i == 4) old_loc = gfc_current_locus; } while (gfc_is_whitespace (c)) c = next_char (); } if (c != '&') { if (in_string) { if (gfc_option.warn_ampersand) gfc_warning_now ("Missing '&' in continued character " "constant at %C"); gfc_current_locus.nextc--; } /* Both !$omp and !$ -fopenmp continuation lines have & on the continuation line only optionally. */ else if (openmp_flag || openmp_cond_flag) gfc_current_locus.nextc--; else { c = ' '; gfc_current_locus = old_loc; goto done; } } } else /* Fixed form. */ { /* Fixed form continuation. */ if (!in_string && c == '!') { /* Skip comment at end of line. */ do { c = next_char (); } while (c != '\n'); /* Avoid truncation warnings for comment ending lines. */ gfc_current_locus.lb->truncated = 0; } if (c != '\n') goto done; /* Check to see if the continuation line was truncated. */ if (gfc_option.warn_line_truncation && gfc_current_locus.lb != NULL && gfc_current_locus.lb->truncated) { gfc_current_locus.lb->truncated = 0; gfc_warning_now ("Line truncated at %L", &gfc_current_locus); } prev_openmp_flag = openmp_flag; continue_flag = 1; old_loc = gfc_current_locus; gfc_advance_line (); skip_fixed_comments (); /* See if this line is a continuation line. */ if (openmp_flag != prev_openmp_flag) { openmp_flag = prev_openmp_flag; goto not_continuation; } if (!openmp_flag) for (i = 0; i < 5; i++) { c = next_char (); if (c != ' ') goto not_continuation; } else for (i = 0; i < 5; i++) { c = next_char (); if (gfc_wide_tolower (c) != (unsigned char) "*$omp"[i]) goto not_continuation; } c = next_char (); if (c == '0' || c == ' ' || c == '\n') goto not_continuation; /* We've got a continuation line. If we are on the very next line after the last continuation, increment the continuation line count and check whether the limit has been exceeded. */ if (gfc_linebuf_linenum (gfc_current_locus.lb) == continue_line + 1) { if (++continue_count == gfc_option.max_continue_fixed) { if (gfc_notification_std (GFC_STD_GNU) || pedantic) gfc_warning ("Limit of %d continuations exceeded in " "statement at %C", gfc_option.max_continue_fixed); } } if (gfc_current_locus.lb != NULL && continue_line < gfc_linebuf_linenum (gfc_current_locus.lb)) continue_line = gfc_linebuf_linenum (gfc_current_locus.lb); } /* Ready to read first character of continuation line, which might be another continuation line! */ goto restart; not_continuation: c = '\n'; gfc_current_locus = old_loc; done: if (c == '\n') continue_count = 0; continue_flag = 0; return c; } /* Get the next character of input, folded to lowercase. In fixed form mode, we also ignore spaces. When matcher subroutines are parsing character literals, they have to call gfc_next_char_literal(). */ gfc_char_t gfc_next_char (void) { gfc_char_t c; do { c = gfc_next_char_literal (0); } while (gfc_current_form == FORM_FIXED && gfc_is_whitespace (c)); return gfc_wide_tolower (c); } char gfc_next_ascii_char (void) { gfc_char_t c = gfc_next_char (); return (gfc_wide_fits_in_byte (c) ? (unsigned char) c : (unsigned char) UCHAR_MAX); } gfc_char_t gfc_peek_char (void) { locus old_loc; gfc_char_t c; old_loc = gfc_current_locus; c = gfc_next_char (); gfc_current_locus = old_loc; return c; } char gfc_peek_ascii_char (void) { gfc_char_t c = gfc_peek_char (); return (gfc_wide_fits_in_byte (c) ? (unsigned char) c : (unsigned char) UCHAR_MAX); } /* Recover from an error. We try to get past the current statement and get lined up for the next. The next statement follows a '\n' or a ';'. We also assume that we are not within a character constant, and deal with finding a '\'' or '"'. */ void gfc_error_recovery (void) { gfc_char_t c, delim; if (gfc_at_eof ()) return; for (;;) { c = gfc_next_char (); if (c == '\n' || c == ';') break; if (c != '\'' && c != '"') { if (gfc_at_eof ()) break; continue; } delim = c; for (;;) { c = next_char (); if (c == delim) break; if (c == '\n') return; if (c == '\\') { c = next_char (); if (c == '\n') return; } } if (gfc_at_eof ()) break; } } /* Read ahead until the next character to be read is not whitespace. */ void gfc_gobble_whitespace (void) { static int linenum = 0; locus old_loc; gfc_char_t c; do { old_loc = gfc_current_locus; c = gfc_next_char_literal (0); /* Issue a warning for nonconforming tabs. We keep track of the line number because the Fortran matchers will often back up and the same line will be scanned multiple times. */ if (!gfc_option.warn_tabs && c == '\t') { int cur_linenum = LOCATION_LINE (gfc_current_locus.lb->location); if (cur_linenum != linenum) { linenum = cur_linenum; gfc_warning_now ("Nonconforming tab character at %C"); } } } while (gfc_is_whitespace (c)); gfc_current_locus = old_loc; } /* Load a single line into pbuf. If pbuf points to a NULL pointer, it is allocated. We truncate lines that are too long, unless we're dealing with preprocessor lines or if the option -ffixed-line-length-none is set, in which case we reallocate the buffer to fit the entire line, if need be. In fixed mode, we expand a tab that occurs within the statement label region to expand to spaces that leave the next character in the source region. If first_char is not NULL, it's a pointer to a single char value holding the first character of the line, which has already been read by the caller. This avoids the use of ungetc(). load_line returns whether the line was truncated. NOTE: The error machinery isn't available at this point, so we can't easily report line and column numbers consistent with other parts of gfortran. */ static int load_line (FILE *input, gfc_char_t **pbuf, int *pbuflen, const int *first_char) { static int linenum = 0, current_line = 1; int c, maxlen, i, preprocessor_flag, buflen = *pbuflen; int trunc_flag = 0, seen_comment = 0; int seen_printable = 0, seen_ampersand = 0; gfc_char_t *buffer; bool found_tab = false; /* Determine the maximum allowed line length. */ if (gfc_current_form == FORM_FREE) maxlen = gfc_option.free_line_length; else if (gfc_current_form == FORM_FIXED) maxlen = gfc_option.fixed_line_length; else maxlen = 72; if (*pbuf == NULL) { /* Allocate the line buffer, storing its length into buflen. Note that if maxlen==0, indicating that arbitrary-length lines are allowed, the buffer will be reallocated if this length is insufficient; since 132 characters is the length of a standard free-form line, we use that as a starting guess. */ if (maxlen > 0) buflen = maxlen; else buflen = 132; *pbuf = gfc_get_wide_string (buflen + 1); } i = 0; buffer = *pbuf; if (first_char) c = *first_char; else c = getc (input); /* In order to not truncate preprocessor lines, we have to remember that this is one. */ preprocessor_flag = (c == '#' ? 1 : 0); for (;;) { if (c == EOF) break; if (c == '\n') { /* Check for illegal use of ampersand. See F95 Standard 3.3.1.3. */ if (gfc_current_form == FORM_FREE && !seen_printable && seen_ampersand) { if (pedantic) gfc_error_now ("'&' not allowed by itself in line %d", current_line); else gfc_warning_now ("'&' not allowed by itself in line %d", current_line); } break; } if (c == '\r' || c == '\0') goto next_char; /* Gobble characters. */ if (c == '&') { if (seen_ampersand) { seen_ampersand = 0; seen_printable = 1; } else seen_ampersand = 1; } if ((c != '&' && c != '!' && c != ' ') || (c == '!' && !seen_ampersand)) seen_printable = 1; /* Is this a fixed-form comment? */ if (gfc_current_form == FORM_FIXED && i == 0 && (c == '*' || c == 'c' || c == 'd')) seen_comment = 1; /* Vendor extension: "<tab>1" marks a continuation line. */ if (found_tab) { found_tab = false; if (c >= '1' && c <= '9') { *(buffer-1) = c; goto next_char; } } if (gfc_current_form == FORM_FIXED && c == '\t' && i < 6) { found_tab = true; if (!gfc_option.warn_tabs && seen_comment == 0 && current_line != linenum) { linenum = current_line; gfc_warning_now ("Nonconforming tab character in column %d " "of line %d", i+1, linenum); } while (i < 6) { *buffer++ = ' '; i++; } goto next_char; } *buffer++ = c; i++; if (maxlen == 0 || preprocessor_flag) { if (i >= buflen) { /* Reallocate line buffer to double size to hold the overlong line. */ buflen = buflen * 2; *pbuf = XRESIZEVEC (gfc_char_t, *pbuf, (buflen + 1)); buffer = (*pbuf) + i; } } else if (i >= maxlen) { /* Truncate the rest of the line. */ for (;;) { c = getc (input); if (c == '\r') continue; if (c == '\n' || c == EOF) break; trunc_flag = 1; } c = '\n'; continue; } next_char: c = getc (input); } /* Pad lines to the selected line length in fixed form. */ if (gfc_current_form == FORM_FIXED && gfc_option.fixed_line_length != 0 && !preprocessor_flag && c != EOF) { while (i++ < maxlen) *buffer++ = ' '; } *buffer = '\0'; *pbuflen = buflen; current_line++; return trunc_flag; } /* Get a gfc_file structure, initialize it and add it to the file stack. */ static gfc_file * get_file (const char *name, enum lc_reason reason ATTRIBUTE_UNUSED) { gfc_file *f; f = XCNEW (gfc_file); f->filename = xstrdup (name); f->next = file_head; file_head = f; f->up = current_file; if (current_file != NULL) f->inclusion_line = current_file->line; linemap_add (line_table, reason, false, f->filename, 1); return f; } /* Deal with a line from the C preprocessor. The initial octothorp has already been seen. */ static void preprocessor_line (gfc_char_t *c) { bool flag[5]; int i, line; gfc_char_t *wide_filename; gfc_file *f; int escaped, unescape; char *filename; c++; while (*c == ' ' || *c == '\t') c++; if (*c < '0' || *c > '9') goto bad_cpp_line; line = wide_atoi (c); c = wide_strchr (c, ' '); if (c == NULL) { /* No file name given. Set new line number. */ current_file->line = line; return; } /* Skip spaces. */ while (*c == ' ' || *c == '\t') c++; /* Skip quote. */ if (*c != '"') goto bad_cpp_line; ++c; wide_filename = c; /* Make filename end at quote. */ unescape = 0; escaped = false; while (*c && ! (!escaped && *c == '"')) { if (escaped) escaped = false; else if (*c == '\\') { escaped = true; unescape++; } ++c; } if (! *c) /* Preprocessor line has no closing quote. */ goto bad_cpp_line; *c++ = '\0'; /* Undo effects of cpp_quote_string. */ if (unescape) { gfc_char_t *s = wide_filename; gfc_char_t *d = gfc_get_wide_string (c - wide_filename - unescape); wide_filename = d; while (*s) { if (*s == '\\') *d++ = *++s; else *d++ = *s; s++; } *d = '\0'; } /* Get flags. */ flag[1] = flag[2] = flag[3] = flag[4] = false; for (;;) { c = wide_strchr (c, ' '); if (c == NULL) break; c++; i = wide_atoi (c); if (1 <= i && i <= 4) flag[i] = true; } /* Convert the filename in wide characters into a filename in narrow characters. */ filename = gfc_widechar_to_char (wide_filename, -1); /* Interpret flags. */ if (flag[1]) /* Starting new file. */ { f = get_file (filename, LC_RENAME); add_file_change (f->filename, f->inclusion_line); current_file = f; } if (flag[2]) /* Ending current file. */ { if (!current_file->up || strcmp (current_file->up->filename, filename) != 0) { gfc_warning_now ("%s:%d: file %s left but not entered", current_file->filename, current_file->line, filename); if (unescape) gfc_free (wide_filename); gfc_free (filename); return; } add_file_change (NULL, line); current_file = current_file->up; linemap_add (line_table, LC_RENAME, false, current_file->filename, current_file->line); } /* The name of the file can be a temporary file produced by cpp. Replace the name if it is different. */ if (strcmp (current_file->filename, filename) != 0) { /* FIXME: we leak the old filename because a pointer to it may be stored in the linemap. Alternative could be using GC or updating linemap to point to the new name, but there is no API for that currently. */ current_file->filename = xstrdup (filename); } /* Set new line number. */ current_file->line = line; if (unescape) gfc_free (wide_filename); gfc_free (filename); return; bad_cpp_line: gfc_warning_now ("%s:%d: Illegal preprocessor directive", current_file->filename, current_file->line); current_file->line++; } static gfc_try load_file (const char *, const char *, bool); /* include_line()-- Checks a line buffer to see if it is an include line. If so, we call load_file() recursively to load the included file. We never return a syntax error because a statement like "include = 5" is perfectly legal. We return false if no include was processed or true if we matched an include. */ static bool include_line (gfc_char_t *line) { gfc_char_t quote, *c, *begin, *stop; char *filename; c = line; if (gfc_option.flag_openmp) { if (gfc_current_form == FORM_FREE) { while (*c == ' ' || *c == '\t') c++; if (*c == '!' && c[1] == '$' && (c[2] == ' ' || c[2] == '\t')) c += 3; } else { if ((*c == '!' || *c == 'c' || *c == 'C' || *c == '*') && c[1] == '$' && (c[2] == ' ' || c[2] == '\t')) c += 3; } } while (*c == ' ' || *c == '\t') c++; if (gfc_wide_strncasecmp (c, "include", 7)) return false; c += 7; while (*c == ' ' || *c == '\t') c++; /* Find filename between quotes. */ quote = *c++; if (quote != '"' && quote != '\'') return false; begin = c; while (*c != quote && *c != '\0') c++; if (*c == '\0') return false; stop = c++; while (*c == ' ' || *c == '\t') c++; if (*c != '\0' && *c != '!') return false; /* We have an include line at this point. */ *stop = '\0'; /* It's ok to trash the buffer, as this line won't be read by anything else. */ filename = gfc_widechar_to_char (begin, -1); load_file (filename, NULL, false); gfc_free (filename); return true; } /* Load a file into memory by calling load_line until the file ends. */ static gfc_try load_file (const char *realfilename, const char *displayedname, bool initial) { gfc_char_t *line; gfc_linebuf *b; gfc_file *f; FILE *input; int len, line_len; bool first_line; const char *filename; filename = displayedname ? displayedname : realfilename; for (f = current_file; f; f = f->up) if (strcmp (filename, f->filename) == 0) { fprintf (stderr, "%s:%d: Error: File '%s' is being included " "recursively\n", current_file->filename, current_file->line, filename); return FAILURE; } if (initial) { if (gfc_src_file) { input = gfc_src_file; gfc_src_file = NULL; } else input = gfc_open_file (realfilename); if (input == NULL) { gfc_error_now ("Can't open file '%s'", filename); return FAILURE; } } else { input = gfc_open_included_file (realfilename, false, false); if (input == NULL) { fprintf (stderr, "%s:%d: Error: Can't open included file '%s'\n", current_file->filename, current_file->line, filename); return FAILURE; } } /* Load the file. */ f = get_file (filename, initial ? LC_RENAME : LC_ENTER); if (!initial) add_file_change (f->filename, f->inclusion_line); current_file = f; current_file->line = 1; line = NULL; line_len = 0; first_line = true; if (initial && gfc_src_preprocessor_lines[0]) { preprocessor_line (gfc_src_preprocessor_lines[0]); gfc_free (gfc_src_preprocessor_lines[0]); gfc_src_preprocessor_lines[0] = NULL; if (gfc_src_preprocessor_lines[1]) { preprocessor_line (gfc_src_preprocessor_lines[1]); gfc_free (gfc_src_preprocessor_lines[1]); gfc_src_preprocessor_lines[1] = NULL; } } for (;;) { int trunc = load_line (input, &line, &line_len, NULL); len = gfc_wide_strlen (line); if (feof (input) && len == 0) break; /* If this is the first line of the file, it can contain a byte order mark (BOM), which we will ignore: FF FE is UTF-16 little endian, FE FF is UTF-16 big endian, EF BB BF is UTF-8. */ if (first_line && ((line_len >= 2 && line[0] == (unsigned char) '\xFF' && line[1] == (unsigned char) '\xFE') || (line_len >= 2 && line[0] == (unsigned char) '\xFE' && line[1] == (unsigned char) '\xFF') || (line_len >= 3 && line[0] == (unsigned char) '\xEF' && line[1] == (unsigned char) '\xBB' && line[2] == (unsigned char) '\xBF'))) { int n = line[1] == (unsigned char) '\xBB' ? 3 : 2; gfc_char_t *new_char = gfc_get_wide_string (line_len); wide_strcpy (new_char, &line[n]); gfc_free (line); line = new_char; len -= n; } /* There are three things this line can be: a line of Fortran source, an include line or a C preprocessor directive. */ if (line[0] == '#') { /* When -g3 is specified, it's possible that we emit #define and #undef lines, which we need to pass to the middle-end so that it can emit correct debug info. */ if (debug_info_level == DINFO_LEVEL_VERBOSE && (wide_strncmp (line, "#define ", 8) == 0 || wide_strncmp (line, "#undef ", 7) == 0)) ; else { preprocessor_line (line); continue; } } /* Preprocessed files have preprocessor lines added before the byte order mark, so first_line is not about the first line of the file but the first line that's not a preprocessor line. */ first_line = false; if (include_line (line)) { current_file->line++; continue; } /* Add line. */ b = (gfc_linebuf *) gfc_getmem (gfc_linebuf_header_size + (len + 1) * sizeof (gfc_char_t)); b->location = linemap_line_start (line_table, current_file->line++, 120); b->file = current_file; b->truncated = trunc; wide_strcpy (b->line, line); if (line_head == NULL) line_head = b; else line_tail->next = b; line_tail = b; while (file_changes_cur < file_changes_count) file_changes[file_changes_cur++].lb = b; } /* Release the line buffer allocated in load_line. */ gfc_free (line); fclose (input); if (!initial) add_file_change (NULL, current_file->inclusion_line + 1); current_file = current_file->up; linemap_add (line_table, LC_LEAVE, 0, NULL, 0); return SUCCESS; } /* Open a new file and start scanning from that file. Returns SUCCESS if everything went OK, FAILURE otherwise. If form == FORM_UNKNOWN it tries to determine the source form from the filename, defaulting to free form. */ gfc_try gfc_new_file (void) { gfc_try result; if (gfc_cpp_enabled ()) { result = gfc_cpp_preprocess (gfc_source_file); if (!gfc_cpp_preprocess_only ()) result = load_file (gfc_cpp_temporary_file (), gfc_source_file, true); } else result = load_file (gfc_source_file, NULL, true); gfc_current_locus.lb = line_head; gfc_current_locus.nextc = (line_head == NULL) ? NULL : line_head->line; #if 0 /* Debugging aid. */ for (; line_head; line_head = line_head->next) printf ("%s:%3d %s\n", LOCATION_FILE (line_head->location), LOCATION_LINE (line_head->location), line_head->line); exit (0); #endif return result; } static char * unescape_filename (const char *ptr) { const char *p = ptr, *s; char *d, *ret; int escaped, unescape = 0; /* Make filename end at quote. */ escaped = false; while (*p && ! (! escaped && *p == '"')) { if (escaped) escaped = false; else if (*p == '\\') { escaped = true; unescape++; } ++p; } if (!*p || p[1]) return NULL; /* Undo effects of cpp_quote_string. */ s = ptr; d = XCNEWVEC (char, p + 1 - ptr - unescape); ret = d; while (s != p) { if (*s == '\\') *d++ = *++s; else *d++ = *s; s++; } *d = '\0'; return ret; } /* For preprocessed files, if the first tokens are of the form # NUM. handle the directives so we know the original file name. */ const char * gfc_read_orig_filename (const char *filename, const char **canon_source_file) { int c, len; char *dirname, *tmp; gfc_src_file = gfc_open_file (filename); if (gfc_src_file == NULL) return NULL; c = getc (gfc_src_file); if (c != '#') return NULL; len = 0; load_line (gfc_src_file, &gfc_src_preprocessor_lines[0], &len, &c); if (wide_strncmp (gfc_src_preprocessor_lines[0], "# 1 \"", 5) != 0) return NULL; tmp = gfc_widechar_to_char (&gfc_src_preprocessor_lines[0][5], -1); filename = unescape_filename (tmp); gfc_free (tmp); if (filename == NULL) return NULL; c = getc (gfc_src_file); if (c != '#') return filename; len = 0; load_line (gfc_src_file, &gfc_src_preprocessor_lines[1], &len, &c); if (wide_strncmp (gfc_src_preprocessor_lines[1], "# 1 \"", 5) != 0) return filename; tmp = gfc_widechar_to_char (&gfc_src_preprocessor_lines[1][5], -1); dirname = unescape_filename (tmp); gfc_free (tmp); if (dirname == NULL) return filename; len = strlen (dirname); if (len < 3 || dirname[len - 1] != '/' || dirname[len - 2] != '/') { gfc_free (dirname); return filename; } dirname[len - 2] = '\0'; set_src_pwd (dirname); if (! IS_ABSOLUTE_PATH (filename)) { char *p = XCNEWVEC (char, len + strlen (filename)); memcpy (p, dirname, len - 2); p[len - 2] = '/'; strcpy (p + len - 1, filename); *canon_source_file = p; } gfc_free (dirname); return filename; }