mirror of https://github.com/python/cpython
850 lines
24 KiB
C
850 lines
24 KiB
C
/* Frame object implementation */
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#include "Python.h"
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#include "code.h"
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#include "frameobject.h"
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#include "opcode.h"
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#include "structmember.h"
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#undef MIN
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#undef MAX
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#define MIN(a, b) ((a) < (b) ? (a) : (b))
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#define MAX(a, b) ((a) > (b) ? (a) : (b))
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#define OFF(x) offsetof(PyFrameObject, x)
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static PyMemberDef frame_memberlist[] = {
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{"f_back", T_OBJECT, OFF(f_back), RO},
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{"f_code", T_OBJECT, OFF(f_code), RO},
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{"f_builtins", T_OBJECT, OFF(f_builtins),RO},
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{"f_globals", T_OBJECT, OFF(f_globals), RO},
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{"f_lasti", T_INT, OFF(f_lasti), RO},
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{"f_exc_type", T_OBJECT, OFF(f_exc_type)},
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{"f_exc_value", T_OBJECT, OFF(f_exc_value)},
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{"f_exc_traceback", T_OBJECT, OFF(f_exc_traceback)},
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{NULL} /* Sentinel */
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};
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static PyObject *
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frame_getlocals(PyFrameObject *f, void *closure)
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{
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PyFrame_FastToLocals(f);
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Py_INCREF(f->f_locals);
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return f->f_locals;
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}
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static PyObject *
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frame_getlineno(PyFrameObject *f, void *closure)
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{
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int lineno;
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if (f->f_trace)
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lineno = f->f_lineno;
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else
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lineno = PyCode_Addr2Line(f->f_code, f->f_lasti);
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return PyInt_FromLong(lineno);
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}
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/* Setter for f_lineno - you can set f_lineno from within a trace function in
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* order to jump to a given line of code, subject to some restrictions. Most
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* lines are OK to jump to because they don't make any assumptions about the
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* state of the stack (obvious because you could remove the line and the code
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* would still work without any stack errors), but there are some constructs
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* that limit jumping:
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*
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* o Lines with an 'except' statement on them can't be jumped to, because
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* they expect an exception to be on the top of the stack.
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* o Lines that live in a 'finally' block can't be jumped from or to, since
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* the END_FINALLY expects to clean up the stack after the 'try' block.
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* o 'try'/'for'/'while' blocks can't be jumped into because the blockstack
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* needs to be set up before their code runs, and for 'for' loops the
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* iterator needs to be on the stack.
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*/
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static int
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frame_setlineno(PyFrameObject *f, PyObject* p_new_lineno)
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{
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int new_lineno = 0; /* The new value of f_lineno */
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int new_lasti = 0; /* The new value of f_lasti */
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int new_iblock = 0; /* The new value of f_iblock */
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char *code = NULL; /* The bytecode for the frame... */
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Py_ssize_t code_len = 0; /* ...and its length */
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char *lnotab = NULL; /* Iterating over co_lnotab */
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Py_ssize_t lnotab_len = 0; /* (ditto) */
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int offset = 0; /* (ditto) */
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int line = 0; /* (ditto) */
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int addr = 0; /* (ditto) */
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int min_addr = 0; /* Scanning the SETUPs and POPs */
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int max_addr = 0; /* (ditto) */
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int delta_iblock = 0; /* (ditto) */
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int min_delta_iblock = 0; /* (ditto) */
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int min_iblock = 0; /* (ditto) */
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int f_lasti_setup_addr = 0; /* Policing no-jump-into-finally */
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int new_lasti_setup_addr = 0; /* (ditto) */
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int blockstack[CO_MAXBLOCKS]; /* Walking the 'finally' blocks */
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int in_finally[CO_MAXBLOCKS]; /* (ditto) */
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int blockstack_top = 0; /* (ditto) */
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int setup_op = 0; /* (ditto) */
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/* f_lineno must be an integer. */
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if (!PyInt_CheckExact(p_new_lineno)) {
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PyErr_SetString(PyExc_ValueError,
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"lineno must be an integer");
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return -1;
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}
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/* You can only do this from within a trace function, not via
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* _getframe or similar hackery. */
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if (!f->f_trace)
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{
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PyErr_Format(PyExc_ValueError,
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"f_lineno can only be set by a trace function");
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return -1;
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}
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/* Fail if the line comes before the start of the code block. */
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new_lineno = (int) PyInt_AsLong(p_new_lineno);
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if (new_lineno < f->f_code->co_firstlineno) {
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PyErr_Format(PyExc_ValueError,
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"line %d comes before the current code block",
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new_lineno);
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return -1;
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}
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/* Find the bytecode offset for the start of the given line, or the
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* first code-owning line after it. */
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PyString_AsStringAndSize(f->f_code->co_lnotab, &lnotab, &lnotab_len);
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addr = 0;
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line = f->f_code->co_firstlineno;
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new_lasti = -1;
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for (offset = 0; offset < lnotab_len; offset += 2) {
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addr += lnotab[offset];
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line += lnotab[offset+1];
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if (line >= new_lineno) {
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new_lasti = addr;
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new_lineno = line;
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break;
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}
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}
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/* If we didn't reach the requested line, return an error. */
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if (new_lasti == -1) {
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PyErr_Format(PyExc_ValueError,
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"line %d comes after the current code block",
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new_lineno);
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return -1;
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}
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/* We're now ready to look at the bytecode. */
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PyString_AsStringAndSize(f->f_code->co_code, &code, &code_len);
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min_addr = MIN(new_lasti, f->f_lasti);
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max_addr = MAX(new_lasti, f->f_lasti);
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/* You can't jump onto a line with an 'except' statement on it -
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* they expect to have an exception on the top of the stack, which
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* won't be true if you jump to them. They always start with code
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* that either pops the exception using POP_TOP (plain 'except:'
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* lines do this) or duplicates the exception on the stack using
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* DUP_TOP (if there's an exception type specified). See compile.c,
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* 'com_try_except' for the full details. There aren't any other
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* cases (AFAIK) where a line's code can start with DUP_TOP or
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* POP_TOP, but if any ever appear, they'll be subject to the same
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* restriction (but with a different error message). */
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if (code[new_lasti] == DUP_TOP || code[new_lasti] == POP_TOP) {
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PyErr_SetString(PyExc_ValueError,
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"can't jump to 'except' line as there's no exception");
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return -1;
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}
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/* You can't jump into or out of a 'finally' block because the 'try'
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* block leaves something on the stack for the END_FINALLY to clean
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* up. So we walk the bytecode, maintaining a simulated blockstack.
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* When we reach the old or new address and it's in a 'finally' block
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* we note the address of the corresponding SETUP_FINALLY. The jump
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* is only legal if neither address is in a 'finally' block or
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* they're both in the same one. 'blockstack' is a stack of the
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* bytecode addresses of the SETUP_X opcodes, and 'in_finally' tracks
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* whether we're in a 'finally' block at each blockstack level. */
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f_lasti_setup_addr = -1;
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new_lasti_setup_addr = -1;
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memset(blockstack, '\0', sizeof(blockstack));
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memset(in_finally, '\0', sizeof(in_finally));
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blockstack_top = 0;
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for (addr = 0; addr < code_len; addr++) {
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unsigned char op = code[addr];
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switch (op) {
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case SETUP_LOOP:
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case SETUP_EXCEPT:
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case SETUP_FINALLY:
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blockstack[blockstack_top++] = addr;
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in_finally[blockstack_top-1] = 0;
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break;
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case POP_BLOCK:
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assert(blockstack_top > 0);
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setup_op = code[blockstack[blockstack_top-1]];
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if (setup_op == SETUP_FINALLY) {
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in_finally[blockstack_top-1] = 1;
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}
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else {
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blockstack_top--;
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}
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break;
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case END_FINALLY:
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/* Ignore END_FINALLYs for SETUP_EXCEPTs - they exist
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* in the bytecode but don't correspond to an actual
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* 'finally' block. (If blockstack_top is 0, we must
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* be seeing such an END_FINALLY.) */
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if (blockstack_top > 0) {
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setup_op = code[blockstack[blockstack_top-1]];
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if (setup_op == SETUP_FINALLY) {
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blockstack_top--;
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}
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}
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break;
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}
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/* For the addresses we're interested in, see whether they're
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* within a 'finally' block and if so, remember the address
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* of the SETUP_FINALLY. */
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if (addr == new_lasti || addr == f->f_lasti) {
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int i = 0;
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int setup_addr = -1;
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for (i = blockstack_top-1; i >= 0; i--) {
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if (in_finally[i]) {
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setup_addr = blockstack[i];
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break;
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}
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}
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if (setup_addr != -1) {
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if (addr == new_lasti) {
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new_lasti_setup_addr = setup_addr;
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}
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if (addr == f->f_lasti) {
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f_lasti_setup_addr = setup_addr;
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}
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}
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}
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if (op >= HAVE_ARGUMENT) {
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addr += 2;
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}
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}
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/* Verify that the blockstack tracking code didn't get lost. */
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assert(blockstack_top == 0);
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/* After all that, are we jumping into / out of a 'finally' block? */
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if (new_lasti_setup_addr != f_lasti_setup_addr) {
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PyErr_SetString(PyExc_ValueError,
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"can't jump into or out of a 'finally' block");
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return -1;
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}
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/* Police block-jumping (you can't jump into the middle of a block)
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* and ensure that the blockstack finishes up in a sensible state (by
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* popping any blocks we're jumping out of). We look at all the
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* blockstack operations between the current position and the new
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* one, and keep track of how many blocks we drop out of on the way.
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* By also keeping track of the lowest blockstack position we see, we
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* can tell whether the jump goes into any blocks without coming out
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* again - in that case we raise an exception below. */
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delta_iblock = 0;
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for (addr = min_addr; addr < max_addr; addr++) {
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unsigned char op = code[addr];
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switch (op) {
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case SETUP_LOOP:
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case SETUP_EXCEPT:
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case SETUP_FINALLY:
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delta_iblock++;
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break;
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case POP_BLOCK:
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delta_iblock--;
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break;
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}
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min_delta_iblock = MIN(min_delta_iblock, delta_iblock);
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if (op >= HAVE_ARGUMENT) {
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addr += 2;
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}
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}
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/* Derive the absolute iblock values from the deltas. */
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min_iblock = f->f_iblock + min_delta_iblock;
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if (new_lasti > f->f_lasti) {
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/* Forwards jump. */
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new_iblock = f->f_iblock + delta_iblock;
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}
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else {
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/* Backwards jump. */
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new_iblock = f->f_iblock - delta_iblock;
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}
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/* Are we jumping into a block? */
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if (new_iblock > min_iblock) {
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PyErr_SetString(PyExc_ValueError,
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"can't jump into the middle of a block");
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return -1;
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}
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/* Pop any blocks that we're jumping out of. */
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while (f->f_iblock > new_iblock) {
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PyTryBlock *b = &f->f_blockstack[--f->f_iblock];
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while ((f->f_stacktop - f->f_valuestack) > b->b_level) {
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PyObject *v = (*--f->f_stacktop);
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Py_DECREF(v);
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}
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}
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/* Finally set the new f_lineno and f_lasti and return OK. */
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f->f_lineno = new_lineno;
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f->f_lasti = new_lasti;
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return 0;
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}
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static PyObject *
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frame_gettrace(PyFrameObject *f, void *closure)
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{
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PyObject* trace = f->f_trace;
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if (trace == NULL)
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trace = Py_None;
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Py_INCREF(trace);
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return trace;
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}
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static int
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frame_settrace(PyFrameObject *f, PyObject* v, void *closure)
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{
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/* We rely on f_lineno being accurate when f_trace is set. */
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PyObject* old_value = f->f_trace;
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Py_XINCREF(v);
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f->f_trace = v;
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if (v != NULL)
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f->f_lineno = PyCode_Addr2Line(f->f_code, f->f_lasti);
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Py_XDECREF(old_value);
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return 0;
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}
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static PyObject *
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frame_getrestricted(PyFrameObject *f, void *closure)
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{
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return PyBool_FromLong(PyFrame_IsRestricted(f));
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}
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static PyGetSetDef frame_getsetlist[] = {
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{"f_locals", (getter)frame_getlocals, NULL, NULL},
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{"f_lineno", (getter)frame_getlineno,
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(setter)frame_setlineno, NULL},
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{"f_trace", (getter)frame_gettrace, (setter)frame_settrace, NULL},
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{"f_restricted",(getter)frame_getrestricted,NULL, NULL},
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{0}
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};
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/* Stack frames are allocated and deallocated at a considerable rate.
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In an attempt to improve the speed of function calls, we:
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1. Hold a single "zombie" frame on each code object. This retains
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the allocated and initialised frame object from an invocation of
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the code object. The zombie is reanimated the next time we need a
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frame object for that code object. Doing this saves the malloc/
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realloc required when using a free_list frame that isn't the
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correct size. It also saves some field initialisation.
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In zombie mode, no field of PyFrameObject holds a reference, but
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the following fields are still valid:
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* ob_type, ob_size, f_code, f_valuestack;
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* f_locals, f_trace,
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f_exc_type, f_exc_value, f_exc_traceback are NULL;
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* f_localsplus does not require re-allocation and
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the local variables in f_localsplus are NULL.
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2. We also maintain a separate free list of stack frames (just like
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integers are allocated in a special way -- see intobject.c). When
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a stack frame is on the free list, only the following members have
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a meaning:
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ob_type == &Frametype
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f_back next item on free list, or NULL
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f_stacksize size of value stack
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ob_size size of localsplus
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Note that the value and block stacks are preserved -- this can save
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another malloc() call or two (and two free() calls as well!).
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Also note that, unlike for integers, each frame object is a
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malloc'ed object in its own right -- it is only the actual calls to
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malloc() that we are trying to save here, not the administration.
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After all, while a typical program may make millions of calls, a
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call depth of more than 20 or 30 is probably already exceptional
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unless the program contains run-away recursion. I hope.
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Later, MAXFREELIST was added to bound the # of frames saved on
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free_list. Else programs creating lots of cyclic trash involving
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frames could provoke free_list into growing without bound.
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*/
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static PyFrameObject *free_list = NULL;
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static int numfree = 0; /* number of frames currently in free_list */
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#define MAXFREELIST 200 /* max value for numfree */
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static void
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frame_dealloc(PyFrameObject *f)
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{
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PyObject **p, **valuestack;
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PyCodeObject *co;
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PyObject_GC_UnTrack(f);
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Py_TRASHCAN_SAFE_BEGIN(f)
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/* Kill all local variables */
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valuestack = f->f_valuestack;
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for (p = f->f_localsplus; p < valuestack; p++)
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Py_CLEAR(*p);
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/* Free stack */
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if (f->f_stacktop != NULL) {
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for (p = valuestack; p < f->f_stacktop; p++)
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Py_XDECREF(*p);
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}
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Py_XDECREF(f->f_back);
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Py_DECREF(f->f_builtins);
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Py_DECREF(f->f_globals);
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Py_CLEAR(f->f_locals);
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Py_CLEAR(f->f_trace);
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Py_CLEAR(f->f_exc_type);
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Py_CLEAR(f->f_exc_value);
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Py_CLEAR(f->f_exc_traceback);
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co = f->f_code;
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if (co->co_zombieframe == NULL)
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co->co_zombieframe = f;
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else if (numfree < MAXFREELIST) {
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++numfree;
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f->f_back = free_list;
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free_list = f;
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}
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else
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PyObject_GC_Del(f);
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Py_DECREF(co);
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Py_TRASHCAN_SAFE_END(f)
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}
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static int
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frame_traverse(PyFrameObject *f, visitproc visit, void *arg)
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{
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PyObject **fastlocals, **p;
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int i, slots;
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Py_VISIT(f->f_back);
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Py_VISIT(f->f_code);
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Py_VISIT(f->f_builtins);
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Py_VISIT(f->f_globals);
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Py_VISIT(f->f_locals);
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Py_VISIT(f->f_trace);
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Py_VISIT(f->f_exc_type);
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Py_VISIT(f->f_exc_value);
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Py_VISIT(f->f_exc_traceback);
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/* locals */
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slots = f->f_code->co_nlocals + PyTuple_GET_SIZE(f->f_code->co_cellvars) + PyTuple_GET_SIZE(f->f_code->co_freevars);
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fastlocals = f->f_localsplus;
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for (i = slots; --i >= 0; ++fastlocals)
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Py_VISIT(*fastlocals);
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/* stack */
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if (f->f_stacktop != NULL) {
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for (p = f->f_valuestack; p < f->f_stacktop; p++)
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Py_VISIT(*p);
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}
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return 0;
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}
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static void
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frame_clear(PyFrameObject *f)
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{
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PyObject **fastlocals, **p, **oldtop;
|
|
int i, slots;
|
|
|
|
/* Before anything else, make sure that this frame is clearly marked
|
|
* as being defunct! Else, e.g., a generator reachable from this
|
|
* frame may also point to this frame, believe itself to still be
|
|
* active, and try cleaning up this frame again.
|
|
*/
|
|
oldtop = f->f_stacktop;
|
|
f->f_stacktop = NULL;
|
|
|
|
Py_CLEAR(f->f_exc_type);
|
|
Py_CLEAR(f->f_exc_value);
|
|
Py_CLEAR(f->f_exc_traceback);
|
|
Py_CLEAR(f->f_trace);
|
|
|
|
/* locals */
|
|
slots = f->f_code->co_nlocals + PyTuple_GET_SIZE(f->f_code->co_cellvars) + PyTuple_GET_SIZE(f->f_code->co_freevars);
|
|
fastlocals = f->f_localsplus;
|
|
for (i = slots; --i >= 0; ++fastlocals)
|
|
Py_CLEAR(*fastlocals);
|
|
|
|
/* stack */
|
|
if (oldtop != NULL) {
|
|
for (p = f->f_valuestack; p < oldtop; p++)
|
|
Py_CLEAR(*p);
|
|
}
|
|
}
|
|
|
|
|
|
PyTypeObject PyFrame_Type = {
|
|
PyObject_HEAD_INIT(&PyType_Type)
|
|
0,
|
|
"frame",
|
|
sizeof(PyFrameObject),
|
|
sizeof(PyObject *),
|
|
(destructor)frame_dealloc, /* tp_dealloc */
|
|
0, /* tp_print */
|
|
0, /* tp_getattr */
|
|
0, /* tp_setattr */
|
|
0, /* tp_compare */
|
|
0, /* tp_repr */
|
|
0, /* tp_as_number */
|
|
0, /* tp_as_sequence */
|
|
0, /* tp_as_mapping */
|
|
0, /* tp_hash */
|
|
0, /* tp_call */
|
|
0, /* tp_str */
|
|
PyObject_GenericGetAttr, /* tp_getattro */
|
|
PyObject_GenericSetAttr, /* tp_setattro */
|
|
0, /* tp_as_buffer */
|
|
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
|
|
0, /* tp_doc */
|
|
(traverseproc)frame_traverse, /* tp_traverse */
|
|
(inquiry)frame_clear, /* tp_clear */
|
|
0, /* tp_richcompare */
|
|
0, /* tp_weaklistoffset */
|
|
0, /* tp_iter */
|
|
0, /* tp_iternext */
|
|
0, /* tp_methods */
|
|
frame_memberlist, /* tp_members */
|
|
frame_getsetlist, /* tp_getset */
|
|
0, /* tp_base */
|
|
0, /* tp_dict */
|
|
};
|
|
|
|
static PyObject *builtin_object;
|
|
|
|
int _PyFrame_Init()
|
|
{
|
|
builtin_object = PyString_InternFromString("__builtins__");
|
|
return (builtin_object != NULL);
|
|
}
|
|
|
|
PyFrameObject *
|
|
PyFrame_New(PyThreadState *tstate, PyCodeObject *code, PyObject *globals,
|
|
PyObject *locals)
|
|
{
|
|
PyFrameObject *back = tstate->frame;
|
|
PyFrameObject *f;
|
|
PyObject *builtins;
|
|
Py_ssize_t i;
|
|
|
|
#ifdef Py_DEBUG
|
|
if (code == NULL || globals == NULL || !PyDict_Check(globals) ||
|
|
(locals != NULL && !PyMapping_Check(locals))) {
|
|
PyErr_BadInternalCall();
|
|
return NULL;
|
|
}
|
|
#endif
|
|
if (back == NULL || back->f_globals != globals) {
|
|
builtins = PyDict_GetItem(globals, builtin_object);
|
|
if (builtins) {
|
|
if (PyModule_Check(builtins)) {
|
|
builtins = PyModule_GetDict(builtins);
|
|
assert(!builtins || PyDict_Check(builtins));
|
|
}
|
|
else if (!PyDict_Check(builtins))
|
|
builtins = NULL;
|
|
}
|
|
if (builtins == NULL) {
|
|
/* No builtins! Make up a minimal one
|
|
Give them 'None', at least. */
|
|
builtins = PyDict_New();
|
|
if (builtins == NULL ||
|
|
PyDict_SetItemString(
|
|
builtins, "None", Py_None) < 0)
|
|
return NULL;
|
|
}
|
|
else
|
|
Py_INCREF(builtins);
|
|
|
|
}
|
|
else {
|
|
/* If we share the globals, we share the builtins.
|
|
Save a lookup and a call. */
|
|
builtins = back->f_builtins;
|
|
assert(builtins != NULL && PyDict_Check(builtins));
|
|
Py_INCREF(builtins);
|
|
}
|
|
if (code->co_zombieframe != NULL) {
|
|
f = code->co_zombieframe;
|
|
code->co_zombieframe = NULL;
|
|
_Py_NewReference((PyObject *)f);
|
|
assert(f->f_code == code);
|
|
}
|
|
else {
|
|
Py_ssize_t extras, ncells, nfrees;
|
|
ncells = PyTuple_GET_SIZE(code->co_cellvars);
|
|
nfrees = PyTuple_GET_SIZE(code->co_freevars);
|
|
extras = code->co_stacksize + code->co_nlocals + ncells +
|
|
nfrees;
|
|
if (free_list == NULL) {
|
|
f = PyObject_GC_NewVar(PyFrameObject, &PyFrame_Type,
|
|
extras);
|
|
if (f == NULL) {
|
|
Py_DECREF(builtins);
|
|
return NULL;
|
|
}
|
|
}
|
|
else {
|
|
assert(numfree > 0);
|
|
--numfree;
|
|
f = free_list;
|
|
free_list = free_list->f_back;
|
|
if (f->ob_size < extras) {
|
|
f = PyObject_GC_Resize(PyFrameObject, f, extras);
|
|
if (f == NULL) {
|
|
Py_DECREF(builtins);
|
|
return NULL;
|
|
}
|
|
}
|
|
_Py_NewReference((PyObject *)f);
|
|
}
|
|
|
|
f->f_code = code;
|
|
extras = code->co_nlocals + ncells + nfrees;
|
|
f->f_valuestack = f->f_localsplus + extras;
|
|
for (i=0; i<extras; i++)
|
|
f->f_localsplus[i] = NULL;
|
|
f->f_locals = NULL;
|
|
f->f_trace = NULL;
|
|
f->f_exc_type = f->f_exc_value = f->f_exc_traceback = NULL;
|
|
}
|
|
f->f_stacktop = f->f_valuestack;
|
|
f->f_builtins = builtins;
|
|
Py_XINCREF(back);
|
|
f->f_back = back;
|
|
Py_INCREF(code);
|
|
Py_INCREF(globals);
|
|
f->f_globals = globals;
|
|
/* Most functions have CO_NEWLOCALS and CO_OPTIMIZED set. */
|
|
if ((code->co_flags & (CO_NEWLOCALS | CO_OPTIMIZED)) ==
|
|
(CO_NEWLOCALS | CO_OPTIMIZED))
|
|
; /* f_locals = NULL; will be set by PyFrame_FastToLocals() */
|
|
else if (code->co_flags & CO_NEWLOCALS) {
|
|
locals = PyDict_New();
|
|
if (locals == NULL) {
|
|
Py_DECREF(f);
|
|
return NULL;
|
|
}
|
|
f->f_locals = locals;
|
|
}
|
|
else {
|
|
if (locals == NULL)
|
|
locals = globals;
|
|
Py_INCREF(locals);
|
|
f->f_locals = locals;
|
|
}
|
|
f->f_tstate = tstate;
|
|
|
|
f->f_lasti = -1;
|
|
f->f_lineno = code->co_firstlineno;
|
|
f->f_iblock = 0;
|
|
|
|
_PyObject_GC_TRACK(f);
|
|
return f;
|
|
}
|
|
|
|
/* Block management */
|
|
|
|
void
|
|
PyFrame_BlockSetup(PyFrameObject *f, int type, int handler, int level)
|
|
{
|
|
PyTryBlock *b;
|
|
if (f->f_iblock >= CO_MAXBLOCKS)
|
|
Py_FatalError("XXX block stack overflow");
|
|
b = &f->f_blockstack[f->f_iblock++];
|
|
b->b_type = type;
|
|
b->b_level = level;
|
|
b->b_handler = handler;
|
|
}
|
|
|
|
PyTryBlock *
|
|
PyFrame_BlockPop(PyFrameObject *f)
|
|
{
|
|
PyTryBlock *b;
|
|
if (f->f_iblock <= 0)
|
|
Py_FatalError("XXX block stack underflow");
|
|
b = &f->f_blockstack[--f->f_iblock];
|
|
return b;
|
|
}
|
|
|
|
/* Convert between "fast" version of locals and dictionary version */
|
|
|
|
static void
|
|
map_to_dict(PyObject *map, Py_ssize_t nmap, PyObject *dict, PyObject **values,
|
|
Py_ssize_t deref)
|
|
{
|
|
Py_ssize_t j;
|
|
for (j = nmap; --j >= 0; ) {
|
|
PyObject *key = PyTuple_GET_ITEM(map, j);
|
|
PyObject *value = values[j];
|
|
if (deref)
|
|
value = PyCell_GET(value);
|
|
if (value == NULL) {
|
|
if (PyObject_DelItem(dict, key) != 0)
|
|
PyErr_Clear();
|
|
}
|
|
else {
|
|
if (PyObject_SetItem(dict, key, value) != 0)
|
|
PyErr_Clear();
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
dict_to_map(PyObject *map, Py_ssize_t nmap, PyObject *dict, PyObject **values,
|
|
Py_ssize_t deref, int clear)
|
|
{
|
|
Py_ssize_t j;
|
|
for (j = nmap; --j >= 0; ) {
|
|
PyObject *key = PyTuple_GET_ITEM(map, j);
|
|
PyObject *value = PyObject_GetItem(dict, key);
|
|
if (value == NULL)
|
|
PyErr_Clear();
|
|
if (deref) {
|
|
if (value || clear) {
|
|
if (PyCell_GET(values[j]) != value) {
|
|
if (PyCell_Set(values[j], value) < 0)
|
|
PyErr_Clear();
|
|
}
|
|
}
|
|
} else if (value != NULL || clear) {
|
|
if (values[j] != value) {
|
|
Py_XINCREF(value);
|
|
Py_XDECREF(values[j]);
|
|
values[j] = value;
|
|
}
|
|
}
|
|
Py_XDECREF(value);
|
|
}
|
|
}
|
|
|
|
void
|
|
PyFrame_FastToLocals(PyFrameObject *f)
|
|
{
|
|
/* Merge fast locals into f->f_locals */
|
|
PyObject *locals, *map;
|
|
PyObject **fast;
|
|
PyObject *error_type, *error_value, *error_traceback;
|
|
PyCodeObject *co;
|
|
Py_ssize_t j;
|
|
int ncells, nfreevars;
|
|
if (f == NULL)
|
|
return;
|
|
locals = f->f_locals;
|
|
if (locals == NULL) {
|
|
locals = f->f_locals = PyDict_New();
|
|
if (locals == NULL) {
|
|
PyErr_Clear(); /* Can't report it :-( */
|
|
return;
|
|
}
|
|
}
|
|
co = f->f_code;
|
|
map = co->co_varnames;
|
|
if (!PyTuple_Check(map))
|
|
return;
|
|
PyErr_Fetch(&error_type, &error_value, &error_traceback);
|
|
fast = f->f_localsplus;
|
|
j = PyTuple_GET_SIZE(map);
|
|
if (j > co->co_nlocals)
|
|
j = co->co_nlocals;
|
|
if (co->co_nlocals)
|
|
map_to_dict(map, j, locals, fast, 0);
|
|
ncells = PyTuple_GET_SIZE(co->co_cellvars);
|
|
nfreevars = PyTuple_GET_SIZE(co->co_freevars);
|
|
if (ncells || nfreevars) {
|
|
map_to_dict(co->co_cellvars, ncells,
|
|
locals, fast + co->co_nlocals, 1);
|
|
map_to_dict(co->co_freevars, nfreevars,
|
|
locals, fast + co->co_nlocals + ncells, 1);
|
|
}
|
|
PyErr_Restore(error_type, error_value, error_traceback);
|
|
}
|
|
|
|
void
|
|
PyFrame_LocalsToFast(PyFrameObject *f, int clear)
|
|
{
|
|
/* Merge f->f_locals into fast locals */
|
|
PyObject *locals, *map;
|
|
PyObject **fast;
|
|
PyObject *error_type, *error_value, *error_traceback;
|
|
PyCodeObject *co;
|
|
Py_ssize_t j;
|
|
int ncells, nfreevars;
|
|
if (f == NULL)
|
|
return;
|
|
locals = f->f_locals;
|
|
co = f->f_code;
|
|
map = co->co_varnames;
|
|
if (locals == NULL)
|
|
return;
|
|
if (!PyTuple_Check(map))
|
|
return;
|
|
PyErr_Fetch(&error_type, &error_value, &error_traceback);
|
|
fast = f->f_localsplus;
|
|
j = PyTuple_GET_SIZE(map);
|
|
if (j > co->co_nlocals)
|
|
j = co->co_nlocals;
|
|
if (co->co_nlocals)
|
|
dict_to_map(co->co_varnames, j, locals, fast, 0, clear);
|
|
ncells = PyTuple_GET_SIZE(co->co_cellvars);
|
|
nfreevars = PyTuple_GET_SIZE(co->co_freevars);
|
|
if (ncells || nfreevars) {
|
|
dict_to_map(co->co_cellvars, ncells,
|
|
locals, fast + co->co_nlocals, 1, clear);
|
|
dict_to_map(co->co_freevars, nfreevars,
|
|
locals, fast + co->co_nlocals + ncells, 1,
|
|
clear);
|
|
}
|
|
PyErr_Restore(error_type, error_value, error_traceback);
|
|
}
|
|
|
|
/* Clear out the free list */
|
|
|
|
void
|
|
PyFrame_Fini(void)
|
|
{
|
|
while (free_list != NULL) {
|
|
PyFrameObject *f = free_list;
|
|
free_list = free_list->f_back;
|
|
PyObject_GC_Del(f);
|
|
--numfree;
|
|
}
|
|
assert(numfree == 0);
|
|
Py_XDECREF(builtin_object);
|
|
builtin_object = NULL;
|
|
}
|