/* Cache of styled source file text
- Copyright (C) 2018-2019 Free Software Foundation, Inc.
+ Copyright (C) 2018-2020 Free Software Foundation, Inc.
This file is part of GDB.
#include "gdbsupport/scoped_fd.h"
#include "source.h"
#include "cli/cli-style.h"
+#include "symtab.h"
+#include "gdbsupport/selftest.h"
+#include "objfiles.h"
+#include "exec.h"
#ifdef HAVE_SOURCE_HIGHLIGHT
/* If Gnulib redirects 'open' and 'close' to its replacements
when GDB is linked. Happens, e.g., in the MinGW build. */
#undef open
#undef close
-#include <fstream>
#include <sstream>
#include <srchilite/sourcehighlight.h>
#include <srchilite/langmap.h>
/* See source-cache.h. */
-bool
-source_cache::get_plain_source_lines (struct symtab *s, int first_line,
- int last_line, std::string *lines)
+std::string
+source_cache::get_plain_source_lines (struct symtab *s,
+ const std::string &fullname)
{
- scoped_fd desc (open_source_file_with_line_charpos (s));
+ scoped_fd desc (open_source_file (s));
if (desc.get () < 0)
- return false;
-
- if (first_line < 1 || first_line > s->nlines || last_line < 1)
- return false;
-
- if (lseek (desc.get (), s->line_charpos[first_line - 1], SEEK_SET) < 0)
perror_with_name (symtab_to_filename_for_display (s));
- int last_charpos;
- if (last_line >= s->nlines)
- {
- struct stat st;
-
- if (fstat (desc.get (), &st) < 0)
- perror_with_name (symtab_to_filename_for_display (s));
- /* We could cache this in line_charpos... */
- last_charpos = st.st_size;
- }
- else
- last_charpos = s->line_charpos[last_line];
+ struct stat st;
+ if (fstat (desc.get (), &st) < 0)
+ perror_with_name (symtab_to_filename_for_display (s));
- lines->resize (last_charpos - s->line_charpos[first_line - 1]);
- if (myread (desc.get (), &(*lines)[0], lines->size ()) < 0)
+ std::string lines;
+ lines.resize (st.st_size);
+ if (myread (desc.get (), &lines[0], lines.size ()) < 0)
perror_with_name (symtab_to_filename_for_display (s));
- return true;
-}
+ time_t mtime = 0;
+ if (SYMTAB_OBJFILE (s) != NULL && SYMTAB_OBJFILE (s)->obfd != NULL)
+ mtime = SYMTAB_OBJFILE (s)->mtime;
+ else if (exec_bfd)
+ mtime = exec_bfd_mtime;
-/* See source-cache.h. */
+ if (mtime && mtime < st.st_mtime)
+ warning (_("Source file is more recent than executable."));
-std::string
-source_cache::extract_lines (const struct source_text &text, int first_line,
- int last_line)
-{
- int lineno = 1;
- std::string::size_type pos = 0;
- std::string::size_type first_pos = std::string::npos;
-
- while (pos != std::string::npos && lineno <= last_line)
+ std::vector<off_t> offsets;
+ offsets.push_back (0);
+ for (size_t offset = lines.find ('\n');
+ offset != std::string::npos;
+ offset = lines.find ('\n', offset))
{
- std::string::size_type new_pos = text.contents.find ('\n', pos);
-
- if (lineno == first_line)
- first_pos = pos;
-
- pos = new_pos;
- if (lineno == last_line || pos == std::string::npos)
- {
- if (first_pos == std::string::npos)
- return {};
- if (pos == std::string::npos)
- pos = text.contents.size ();
- return text.contents.substr (first_pos, pos - first_pos);
- }
- ++lineno;
- ++pos;
+ ++offset;
+ /* A newline at the end does not start a new line. It would
+ seem simpler to just strip the newline in this function, but
+ then "list" won't print the final newline. */
+ if (offset != lines.size ())
+ offsets.push_back (offset);
}
- return {};
+ offsets.shrink_to_fit ();
+ m_offset_cache.emplace (fullname, std::move (offsets));
+
+ return lines;
}
#ifdef HAVE_SOURCE_HIGHLIGHT
break;
case language_rust:
- /* Not handled by Source Highlight. */
- break;
+ return "rust.lang";
case language_ada:
return "ada.lang";
/* See source-cache.h. */
bool
-source_cache::get_source_lines (struct symtab *s, int first_line,
- int last_line, std::string *lines)
+source_cache::ensure (struct symtab *s)
{
- if (first_line < 1 || last_line < 1 || first_line > last_line)
- return false;
+ std::string fullname = symtab_to_fullname (s);
-#ifdef HAVE_SOURCE_HIGHLIGHT
- if (source_styling && gdb_stdout->can_emit_style_escape ())
+ size_t size = m_source_map.size ();
+ for (int i = 0; i < size; ++i)
{
- const char *fullname = symtab_to_fullname (s);
-
- for (const auto &item : m_source_map)
+ if (m_source_map[i].fullname == fullname)
{
- if (item.fullname == fullname)
- {
- *lines = extract_lines (item, first_line, last_line);
- return true;
- }
+ /* This should always hold, because we create the file
+ offsets when reading the file, and never free them
+ without also clearing the contents cache. */
+ gdb_assert (m_offset_cache.find (fullname)
+ != m_offset_cache.end ());
+ /* Not strictly LRU, but at least ensure that the most
+ recently used entry is always the last candidate for
+ deletion. Note that this property is relied upon by at
+ least one caller. */
+ if (i != size - 1)
+ std::swap (m_source_map[i], m_source_map[size - 1]);
+ return true;
}
+ }
+
+ std::string contents;
+ try
+ {
+ contents = get_plain_source_lines (s, fullname);
+ }
+ catch (const gdb_exception_error &e)
+ {
+ /* If 's' is not found, an exception is thrown. */
+ return false;
+ }
+ if (source_styling && gdb_stdout->can_emit_style_escape ())
+ {
+#ifdef HAVE_SOURCE_HIGHLIGHT
+ bool already_styled = false;
const char *lang_name = get_language_name (SYMTAB_LANGUAGE (s));
if (lang_name != nullptr)
{
- std::ifstream input (fullname);
- if (input.is_open ())
- {
- /* The global source highlight object, or null if one
- was never constructed. This is stored here rather
- than in the class so that we don't need to include
- anything or do conditional compilation in
- source-cache.h. */
- static srchilite::SourceHighlight *highlighter;
-
- if (s->line_charpos == 0)
- {
- scoped_fd desc (open_source_file_with_line_charpos (s));
- if (desc.get () < 0)
- return false;
-
- /* FULLNAME points to a value owned by the symtab
- (symtab::fullname). Calling open_source_file reallocates
- that value, so we must refresh FULLNAME to avoid a
- use-after-free. */
- fullname = symtab_to_fullname (s);
- }
+ /* The global source highlight object, or null if one was
+ never constructed. This is stored here rather than in
+ the class so that we don't need to include anything or do
+ conditional compilation in source-cache.h. */
+ static srchilite::SourceHighlight *highlighter;
+ try
+ {
if (highlighter == nullptr)
{
highlighter = new srchilite::SourceHighlight ("esc.outlang");
highlighter->setStyleFile ("esc.style");
}
+ std::istringstream input (contents);
std::ostringstream output;
highlighter->highlight (input, output, lang_name, fullname);
+ contents = output.str ();
+ already_styled = true;
+ }
+ catch (...)
+ {
+ /* Source Highlight will throw an exception if
+ highlighting fails. One possible reason it can fail
+ is if the language is unknown -- which matters to gdb
+ because Rust support wasn't added until after 3.1.8.
+ Ignore exceptions here and fall back to
+ un-highlighted text. */
+ }
+ }
+
+ if (!already_styled)
+#endif /* HAVE_SOURCE_HIGHLIGHT */
+ {
+ gdb::optional<std::string> ext_contents;
+ ext_contents = ext_lang_colorize (fullname, contents);
+ if (ext_contents.has_value ())
+ contents = std::move (*ext_contents);
+ }
+ }
- source_text result = { fullname, output.str () };
- m_source_map.push_back (std::move (result));
+ source_text result = { std::move (fullname), std::move (contents) };
+ m_source_map.push_back (std::move (result));
- if (m_source_map.size () > MAX_ENTRIES)
- m_source_map.erase (m_source_map.begin ());
+ if (m_source_map.size () > MAX_ENTRIES)
+ m_source_map.erase (m_source_map.begin ());
- *lines = extract_lines (m_source_map.back (), first_line,
- last_line);
- return true;
- }
+ return true;
+}
+
+/* See source-cache.h. */
+
+bool
+source_cache::get_line_charpos (struct symtab *s,
+ const std::vector<off_t> **offsets)
+{
+ std::string fullname = symtab_to_fullname (s);
+
+ auto iter = m_offset_cache.find (fullname);
+ if (iter == m_offset_cache.end ())
+ {
+ if (!ensure (s))
+ return false;
+ iter = m_offset_cache.find (fullname);
+ /* cache_source_text ensured this was entered. */
+ gdb_assert (iter != m_offset_cache.end ());
+ }
+
+ *offsets = &iter->second;
+ return true;
+}
+
+/* A helper function that extracts the desired source lines from TEXT,
+ putting them into LINES_OUT. The arguments are as for
+ get_source_lines. Returns true on success, false if the line
+ numbers are invalid. */
+
+static bool
+extract_lines (const std::string &text, int first_line, int last_line,
+ std::string *lines_out)
+{
+ int lineno = 1;
+ std::string::size_type pos = 0;
+ std::string::size_type first_pos = std::string::npos;
+
+ while (pos != std::string::npos && lineno <= last_line)
+ {
+ std::string::size_type new_pos = text.find ('\n', pos);
+
+ if (lineno == first_line)
+ first_pos = pos;
+
+ pos = new_pos;
+ if (lineno == last_line || pos == std::string::npos)
+ {
+ /* A newline at the end does not start a new line. */
+ if (first_pos == std::string::npos
+ || first_pos == text.size ())
+ return false;
+ if (pos == std::string::npos)
+ pos = text.size ();
+ else
+ ++pos;
+ *lines_out = text.substr (first_pos, pos - first_pos);
+ return true;
}
+ ++lineno;
+ ++pos;
}
-#endif /* HAVE_SOURCE_HIGHLIGHT */
- return get_plain_source_lines (s, first_line, last_line, lines);
+ return false;
+}
+
+/* See source-cache.h. */
+
+bool
+source_cache::get_source_lines (struct symtab *s, int first_line,
+ int last_line, std::string *lines)
+{
+ if (first_line < 1 || last_line < 1 || first_line > last_line)
+ return false;
+
+ if (!ensure (s))
+ return false;
+
+ return extract_lines (m_source_map.back ().contents,
+ first_line, last_line, lines);
+}
+
+#if GDB_SELF_TEST
+namespace selftests
+{
+static void extract_lines_test ()
+{
+ std::string input_text = "abc\ndef\nghi\njkl\n";
+ std::string result;
+
+ SELF_CHECK (extract_lines (input_text, 1, 1, &result)
+ && result == "abc\n");
+ SELF_CHECK (!extract_lines (input_text, 2, 1, &result));
+ SELF_CHECK (extract_lines (input_text, 1, 2, &result)
+ && result == "abc\ndef\n");
+ SELF_CHECK (extract_lines ("abc", 1, 1, &result)
+ && result == "abc");
+}
+}
+#endif
+
+void _initialize_source_cache ();
+void
+_initialize_source_cache ()
+{
+#if GDB_SELF_TEST
+ selftests::register_test ("source-cache", selftests::extract_lines_test);
+#endif
}
projects / deliverable / binutils-gdb.git / blobdiff