The Tor Browser: toolkit/crashreporter/google-breakpad/src/common/test

toolkit/crashreporter/google-breakpad/src/common/test_assembler.h@129ffea94266 (annotated)

toolkit/crashreporter/google-breakpad/src/common/test_assembler.h

Sat, 03 Jan 2015 20:18:00 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Sat, 03 Jan 2015 20:18:00 +0100
branch: TOR_BUG_3246
changeset 7: 129ffea94266
permissions: -rw-r--r--

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

 // -*- mode: C++ -*-
 // Copyright (c) 2010, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 // copyright notice, this list of conditions and the following disclaimer
 // in the documentation and/or other materials provided with the
 // distribution.
 //     * Neither the name of Google Inc. nor the names of its
 // contributors may be used to endorse or promote products derived from
 // this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 // Original author: Jim Blandy <jimb@mozilla.com> <jimb@red-bean.com>
 // test-assembler.h: interface to class for building complex binary streams.
 // To test the Breakpad symbol dumper and processor thoroughly, for
 // all combinations of host system and minidump processor
 // architecture, we need to be able to easily generate complex test
 // data like debugging information and minidump files.
 //
 // For example, if we want our unit tests to provide full code
 // coverage for stack walking, it may be difficult to persuade the
 // compiler to generate every possible sort of stack walking
 // information that we want to support; there are probably DWARF CFI
 // opcodes that GCC never emits. Similarly, if we want to test our
 // error handling, we will need to generate damaged minidumps or
 // debugging information that (we hope) the client or compiler will
 // never produce on its own.
 //
 // google_breakpad::TestAssembler provides a predictable and
 // (relatively) simple way to generate complex formatted data streams
 // like minidumps and CFI. Furthermore, because TestAssembler is
 // portable, developers without access to (say) Visual Studio or a
 // SPARC assembler can still work on test data for those targets.
 #ifndef PROCESSOR_TEST_ASSEMBLER_H_
 #define PROCESSOR_TEST_ASSEMBLER_H_
 #include <list>
 #include <vector>
 #include <string>
 #include "common/using_std_string.h"
 #include "google_breakpad/common/breakpad_types.h"
 namespace google_breakpad {
 using std::list;
 using std::vector;
 namespace test_assembler {
 // A Label represents a value not yet known that we need to store in a
 // section. As long as all the labels a section refers to are defined
 // by the time we retrieve its contents as bytes, we can use undefined
 // labels freely in that section's construction.
 //
 // A label can be in one of three states:
 // - undefined,
 // - defined as the sum of some other label and a constant, or
 // - a constant.
 //
 // A label's value never changes, but it can accumulate constraints.
 // Adding labels and integers is permitted, and yields a label.
 // Subtracting a constant from a label is permitted, and also yields a
 // label. Subtracting two labels that have some relationship to each
 // other is permitted, and yields a constant.
 //
 // For example:
 //
 //   Label a;               // a's value is undefined
 //   Label b;               // b's value is undefined
 //   {
 //     Label c = a + 4;     // okay, even though a's value is unknown
 //     b = c + 4;           // also okay; b is now a+8
 //   }
 //   Label d = b - 2;       // okay; d == a+6, even though c is gone
 //   d.Value();             // error: d's value is not yet known
 //   d - a;                 // is 6, even though their values are not known
 //   a = 12;                // now b == 20, and d == 18
 //   d.Value();             // 18: no longer an error
 //   b.Value();             // 20
 //   d = 10;                // error: d is already defined.
 //
 // Label objects' lifetimes are unconstrained: notice that, in the
 // above example, even though a and b are only related through c, and
 // c goes out of scope, the assignment to a sets b's value as well. In
 // particular, it's not necessary to ensure that a Label lives beyond
 // Sections that refer to it.
 class Label {
  public:
   Label();                      // An undefined label.
   Label(uint64_t value);       // A label with a fixed value
   Label(const Label &value);    // A label equal to another.
   ~Label();
   // Return this label's value; it must be known.
   //
   // Providing this as a cast operator is nifty, but the conversions
   // happen in unexpected places. In particular, ISO C++ says that
   // Label + size_t becomes ambigious, because it can't decide whether
   // to convert the Label to a uint64_t and then to a size_t, or use
   // the overloaded operator that returns a new label, even though the
   // former could fail if the label is not yet defined and the latter won't.
   uint64_t Value() const;
   Label &operator=(uint64_t value);
   Label &operator=(const Label &value);
   Label operator+(uint64_t addend) const;
   Label operator-(uint64_t subtrahend) const;
   uint64_t operator-(const Label &subtrahend) const;
   // We could also provide == and != that work on undefined, but
   // related, labels.
   // Return true if this label's value is known. If VALUE_P is given,
   // set *VALUE_P to the known value if returning true.
   bool IsKnownConstant(uint64_t *value_p = NULL) const;
   // Return true if the offset from LABEL to this label is known. If
   // OFFSET_P is given, set *OFFSET_P to the offset when returning true.
   //
   // You can think of l.KnownOffsetFrom(m, &d) as being like 'd = l-m',
   // except that it also returns a value indicating whether the
   // subtraction is possible given what we currently know of l and m.
   // It can be possible even if we don't know l and m's values. For
   // example:
   //
   //   Label l, m;
   //   m = l + 10;
   //   l.IsKnownConstant();             // false
   //   m.IsKnownConstant();             // false
   //   uint64_t d;
   //   l.IsKnownOffsetFrom(m, &d);      // true, and sets d to -10.
   //   l-m                              // -10
   //   m-l                              // 10
   //   m.Value()                        // error: m's value is not known
   bool IsKnownOffsetFrom(const Label &label, uint64_t *offset_p = NULL) const;
  private:
   // A label's value, or if that is not yet known, how the value is
   // related to other labels' values. A binding may be:
   // - a known constant,
   // - constrained to be equal to some other binding plus a constant, or
   // - unconstrained, and free to take on any value.
   //
   // Many labels may point to a single binding, and each binding may
   // refer to another, so bindings and labels form trees whose leaves
   // are labels, whose interior nodes (and roots) are bindings, and
   // where links point from children to parents. Bindings are
   // reference counted, allowing labels to be lightweight, copyable,
   // assignable, placed in containers, and so on.
   class Binding {
    public:
     Binding();
     Binding(uint64_t addend);
     ~Binding();
     // Increment our reference count.
     void Acquire() { reference_count_++; };
     // Decrement our reference count, and return true if it is zero.
     bool Release() { return --reference_count_ == 0; }
     // Set this binding to be equal to BINDING + ADDEND. If BINDING is
     // NULL, then set this binding to the known constant ADDEND.
     // Update every binding on this binding's chain to point directly
     // to BINDING, or to be a constant, with addends adjusted
     // appropriately.
     void Set(Binding *binding, uint64_t value);
     // Return what we know about the value of this binding.
     // - If this binding's value is a known constant, set BASE to
     //   NULL, and set ADDEND to its value.
     // - If this binding is not a known constant but related to other
     //   bindings, set BASE to the binding at the end of the relation
     //   chain (which will always be unconstrained), and set ADDEND to the
     //   value to add to that binding's value to get this binding's
     //   value.
     // - If this binding is unconstrained, set BASE to this, and leave
     //   ADDEND unchanged.
     void Get(Binding **base, uint64_t *addend);
    private:
     // There are three cases:
     //
     // - A binding representing a known constant value has base_ NULL,
     //   and addend_ equal to the value.
     //
     // - A binding representing a completely unconstrained value has
     //   base_ pointing to this; addend_ is unused.
     //
     // - A binding whose value is related to some other binding's
     //   value has base_ pointing to that other binding, and addend_
     //   set to the amount to add to that binding's value to get this
     //   binding's value. We only represent relationships of the form
     //   x = y+c.
     //
     // Thus, the bind_ links form a chain terminating in either a
     // known constant value or a completely unconstrained value. Most
     // operations on bindings do path compression: they change every
     // binding on the chain to point directly to the final value,
     // adjusting addends as appropriate.
     Binding *base_;
     uint64_t addend_;
     // The number of Labels and Bindings pointing to this binding.
     // (When a binding points to itself, indicating a completely
     // unconstrained binding, that doesn't count as a reference.)
     int reference_count_;
   };
   // This label's value.
   Binding *value_;
 };
 inline Label operator+(uint64_t a, const Label &l) { return l + a; }
 // Note that int-Label isn't defined, as negating a Label is not an
 // operation we support.
 // Conventions for representing larger numbers as sequences of bytes.
 enum Endianness {
   kBigEndian,        // Big-endian: the most significant byte comes first.
   kLittleEndian,     // Little-endian: the least significant byte comes first.
   kUnsetEndian,      // used internally
 };
 // A section is a sequence of bytes, constructed by appending bytes
 // to the end. Sections have a convenient and flexible set of member
 // functions for appending data in various formats: big-endian and
 // little-endian signed and unsigned values of different sizes;
 // LEB128 and ULEB128 values (see below), and raw blocks of bytes.
 //
 // If you need to append a value to a section that is not convenient
 // to compute immediately, you can create a label, append the
 // label's value to the section, and then set the label's value
 // later, when it's convenient to do so. Once a label's value is
 // known, the section class takes care of updating all previously
 // appended references to it.
 //
 // Once all the labels to which a section refers have had their
 // values determined, you can get a copy of the section's contents
 // as a string.
 //
 // Note that there is no specified "start of section" label. This is
 // because there are typically several different meanings for "the
 // start of a section": the offset of the section within an object
 // file, the address in memory at which the section's content appear,
 // and so on. It's up to the code that uses the Section class to
 // keep track of these explicitly, as they depend on the application.
 class Section {
  public:
   Section(Endianness endianness = kUnsetEndian)
       : endianness_(endianness) { };
   // A base class destructor should be either public and virtual,
   // or protected and nonvirtual.
   virtual ~Section() { };
   // Set the default endianness of this section to ENDIANNESS. This
   // sets the behavior of the D<N> appending functions. If the
   // assembler's default endianness was set, this is the
   void set_endianness(Endianness endianness) {
     endianness_ = endianness;
   }
   // Return the default endianness of this section.
   Endianness endianness() const { return endianness_; }
   // Append the SIZE bytes at DATA or the contents of STRING to the
   // end of this section. Return a reference to this section.
   Section &Append(const uint8_t *data, size_t size) {
     contents_.append(reinterpret_cast<const char *>(data), size);
     return *this;
   };
   Section &Append(const string &data) {
     contents_.append(data);
     return *this;
   };
   // Append SIZE copies of BYTE to the end of this section. Return a
   // reference to this section.
   Section &Append(size_t size, uint8_t byte) {
     contents_.append(size, (char) byte);
     return *this;
   }
   // Append NUMBER to this section. ENDIANNESS is the endianness to
   // use to write the number. SIZE is the length of the number in
   // bytes. Return a reference to this section.
   Section &Append(Endianness endianness, size_t size, uint64_t number);
   Section &Append(Endianness endianness, size_t size, const Label &label);
   // Append SECTION to the end of this section. The labels SECTION
   // refers to need not be defined yet.
   //
   // Note that this has no effect on any Labels' values, or on
   // SECTION. If placing SECTION within 'this' provides new
   // constraints on existing labels' values, then it's up to the
   // caller to fiddle with those labels as needed.
   Section &Append(const Section &section);
   // Append the contents of DATA as a series of bytes terminated by
   // a NULL character.
   Section &AppendCString(const string &data) {
     Append(data);
     contents_ += '\0';
     return *this;
   }
   // Append at most SIZE bytes from DATA; if DATA is less than SIZE bytes
   // long, pad with '\0' characters.
   Section &AppendCString(const string &data, size_t size) {
     contents_.append(data, 0, size);
     if (data.size() < size)
       Append(size - data.size(), 0);
     return *this;
   }
   // Append VALUE or LABEL to this section, with the given bit width and
   // endianness. Return a reference to this section.
   //
   // The names of these functions have the form <ENDIANNESS><BITWIDTH>:
   // <ENDIANNESS> is either 'L' (little-endian, least significant byte first),
   //                        'B' (big-endian, most significant byte first), or
   //                        'D' (default, the section's default endianness)
   // <BITWIDTH> is 8, 16, 32, or 64.
   //
   // Since endianness doesn't matter for a single byte, all the
   // <BITWIDTH>=8 functions are equivalent.
   //
   // These can be used to write both signed and unsigned values, as
   // the compiler will properly sign-extend a signed value before
   // passing it to the function, at which point the function's
   // behavior is the same either way.
   Section &L8(uint8_t value) { contents_ += value; return *this; }
   Section &B8(uint8_t value) { contents_ += value; return *this; }
   Section &D8(uint8_t value) { contents_ += value; return *this; }
   Section &L16(uint16_t), &L32(uint32_t), &L64(uint64_t),
           &B16(uint16_t), &B32(uint32_t), &B64(uint64_t),
           &D16(uint16_t), &D32(uint32_t), &D64(uint64_t);
   Section &L8(const Label &label),  &L16(const Label &label),
           &L32(const Label &label), &L64(const Label &label),
           &B8(const Label &label),  &B16(const Label &label),
           &B32(const Label &label), &B64(const Label &label),
           &D8(const Label &label),  &D16(const Label &label),
           &D32(const Label &label), &D64(const Label &label);
   // Append VALUE in a signed LEB128 (Little-Endian Base 128) form.
   //
   // The signed LEB128 representation of an integer N is a variable
   // number of bytes:
   //
   // - If N is between -0x40 and 0x3f, then its signed LEB128
   //   representation is a single byte whose value is N.
   //
   // - Otherwise, its signed LEB128 representation is (N & 0x7f) |
   //   0x80, followed by the signed LEB128 representation of N / 128,
   //   rounded towards negative infinity.
   //
   // In other words, we break VALUE into groups of seven bits, put
   // them in little-endian order, and then write them as eight-bit
   // bytes with the high bit on all but the last.
   //
   // Note that VALUE cannot be a Label (we would have to implement
   // relaxation).
   Section &LEB128(long long value);
   // Append VALUE in unsigned LEB128 (Little-Endian Base 128) form.
   //
   // The unsigned LEB128 representation of an integer N is a variable
   // number of bytes:
   //
   // - If N is between 0 and 0x7f, then its unsigned LEB128
   //   representation is a single byte whose value is N.
   //
   // - Otherwise, its unsigned LEB128 representation is (N & 0x7f) |
   //   0x80, followed by the unsigned LEB128 representation of N /
   //   128, rounded towards negative infinity.
   //
   // Note that VALUE cannot be a Label (we would have to implement
   // relaxation).
   Section &ULEB128(uint64_t value);
   // Jump to the next location aligned on an ALIGNMENT-byte boundary,
   // relative to the start of the section. Fill the gap with PAD_BYTE.
   // ALIGNMENT must be a power of two. Return a reference to this
   // section.
   Section &Align(size_t alignment, uint8_t pad_byte = 0);
   // Clear the contents of this section.
   void Clear();
   // Return the current size of the section.
   size_t Size() const { return contents_.size(); }
   // Return a label representing the start of the section.
   //
   // It is up to the user whether this label represents the section's
   // position in an object file, the section's address in memory, or
   // what have you; some applications may need both, in which case
   // this simple-minded interface won't be enough. This class only
   // provides a single start label, for use with the Here and Mark
   // member functions.
   //
   // Ideally, we'd provide this in a subclass that actually knows more
   // about the application at hand and can provide an appropriate
   // collection of start labels. But then the appending member
   // functions like Append and D32 would return a reference to the
   // base class, not the derived class, and the chaining won't work.
   // Since the only value here is in pretty notation, that's a fatal
   // flaw.
   Label start() const { return start_; }
   // Return a label representing the point at which the next Appended
   // item will appear in the section, relative to start().
   Label Here() const { return start_ + Size(); }
   // Set *LABEL to Here, and return a reference to this section.
   Section &Mark(Label *label) { *label = Here(); return *this; }
   // If there are no undefined label references left in this
   // section, set CONTENTS to the contents of this section, as a
   // string, and clear this section. Return true on success, or false
   // if there were still undefined labels.
   bool GetContents(string *contents);
  private:
   // Used internally. A reference to a label's value.
   struct Reference {
     Reference(size_t set_offset, Endianness set_endianness,  size_t set_size,
               const Label &set_label)
         : offset(set_offset), endianness(set_endianness), size(set_size),
           label(set_label) { }
     // The offset of the reference within the section.
     size_t offset;
     // The endianness of the reference.
     Endianness endianness;
     // The size of the reference.
     size_t size;
     // The label to which this is a reference.
     Label label;
   };
   // The default endianness of this section.
   Endianness endianness_;
   // The contents of the section.
   string contents_;
   // References to labels within those contents.
   vector<Reference> references_;
   // A label referring to the beginning of the section.
   Label start_;
 };
 }  // namespace test_assembler
 }  // namespace google_breakpad
 #endif  // PROCESSOR_TEST_ASSEMBLER_H_

The Tor Browser / annotate

toolkit/crashreporter/google-breakpad/src/common/test_assembler.h@129ffea94266 (annotated)

toolkit/crashreporter/google-breakpad/src/common/test_assembler.h