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815 lines
23 KiB
815 lines
23 KiB
|
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/* Frame object implementation */ |
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|
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#include "Python.h" |
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|
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#include "compile.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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|
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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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|
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#define OFF(x) offsetof(PyFrameObject, x) |
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|
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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_restricted",T_INT, OFF(f_restricted),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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|
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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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|
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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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|
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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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|
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return PyInt_FromLong(lineno); |
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} |
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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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int code_len = 0; /* ...and its length */ |
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char *lnotab = NULL; /* Iterating over co_lnotab */ |
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int 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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|
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/* f_lineno must be an integer. */ |
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if (!PyInt_Check(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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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min_delta_iblock = MIN(min_delta_iblock, delta_iblock); |
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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if (trace == NULL) |
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trace = Py_None; |
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|
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Py_INCREF(trace); |
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|
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return trace; |
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} |
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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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|
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PyObject* old_value = f->f_trace; |
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|
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Py_XINCREF(v); |
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f->f_trace = v; |
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|
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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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|
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Py_XDECREF(old_value); |
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|
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return 0; |
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} |
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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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{0} |
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}; |
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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 maintain a |
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separate free list of stack frames (just like integers are |
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allocated in a special way -- see intobject.c). When a stack frame |
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is on the free list, only the following members have 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_nlocals number of locals |
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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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|
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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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|
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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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|
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static void |
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frame_dealloc(PyFrameObject *f) |
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{ |
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int i, slots; |
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PyObject **fastlocals; |
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PyObject **p; |
|
|
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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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slots = f->f_nlocals + f->f_ncells + f->f_nfreevars; |
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fastlocals = f->f_localsplus; |
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for (i = slots; --i >= 0; ++fastlocals) { |
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Py_XDECREF(*fastlocals); |
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} |
|
|
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/* Free 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_XDECREF(*p); |
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} |
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|
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Py_XDECREF(f->f_back); |
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Py_DECREF(f->f_code); |
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Py_DECREF(f->f_builtins); |
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Py_DECREF(f->f_globals); |
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Py_XDECREF(f->f_locals); |
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Py_XDECREF(f->f_trace); |
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Py_XDECREF(f->f_exc_type); |
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Py_XDECREF(f->f_exc_value); |
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Py_XDECREF(f->f_exc_traceback); |
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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_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, err, slots; |
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#define VISIT(o) if (o) {if ((err = visit((PyObject *)(o), arg))) return err;} |
|
|
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VISIT(f->f_back); |
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VISIT(f->f_code); |
|
VISIT(f->f_builtins); |
|
VISIT(f->f_globals); |
|
VISIT(f->f_locals); |
|
VISIT(f->f_trace); |
|
VISIT(f->f_exc_type); |
|
VISIT(f->f_exc_value); |
|
VISIT(f->f_exc_traceback); |
|
|
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/* locals */ |
|
slots = f->f_nlocals + f->f_ncells + f->f_nfreevars; |
|
fastlocals = f->f_localsplus; |
|
for (i = slots; --i >= 0; ++fastlocals) { |
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VISIT(*fastlocals); |
|
} |
|
|
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/* stack */ |
|
if (f->f_stacktop != NULL) { |
|
for (p = f->f_valuestack; p < f->f_stacktop; p++) |
|
VISIT(*p); |
|
} |
|
return 0; |
|
} |
|
|
|
static void |
|
frame_clear(PyFrameObject *f) |
|
{ |
|
PyObject **fastlocals, **p; |
|
int i, slots; |
|
|
|
Py_XDECREF(f->f_exc_type); |
|
f->f_exc_type = NULL; |
|
|
|
Py_XDECREF(f->f_exc_value); |
|
f->f_exc_value = NULL; |
|
|
|
Py_XDECREF(f->f_exc_traceback); |
|
f->f_exc_traceback = NULL; |
|
|
|
Py_XDECREF(f->f_trace); |
|
f->f_trace = NULL; |
|
|
|
/* locals */ |
|
slots = f->f_nlocals + f->f_ncells + f->f_nfreevars; |
|
fastlocals = f->f_localsplus; |
|
for (i = slots; --i >= 0; ++fastlocals) { |
|
if (*fastlocals != NULL) { |
|
Py_XDECREF(*fastlocals); |
|
*fastlocals = NULL; |
|
} |
|
} |
|
|
|
/* stack */ |
|
if (f->f_stacktop != NULL) { |
|
for (p = f->f_valuestack; p < f->f_stacktop; p++) { |
|
Py_XDECREF(*p); |
|
*p = NULL; |
|
} |
|
} |
|
} |
|
|
|
|
|
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; |
|
int extras, ncells, nfrees; |
|
|
|
#ifdef Py_DEBUG |
|
if (code == NULL || globals == NULL || !PyDict_Check(globals) || |
|
(locals != NULL && !PyDict_Check(locals))) { |
|
PyErr_BadInternalCall(); |
|
return NULL; |
|
} |
|
#endif |
|
ncells = PyTuple_GET_SIZE(code->co_cellvars); |
|
nfrees = PyTuple_GET_SIZE(code->co_freevars); |
|
extras = code->co_stacksize + code->co_nlocals + ncells + nfrees; |
|
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 (free_list == NULL) { |
|
f = PyObject_GC_NewVar(PyFrameObject, &PyFrame_Type, extras); |
|
if (f == NULL) |
|
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) |
|
return NULL; |
|
} |
|
_Py_NewReference((PyObject *)f); |
|
} |
|
f->f_builtins = builtins; |
|
Py_XINCREF(back); |
|
f->f_back = back; |
|
Py_INCREF(code); |
|
f->f_code = 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)) |
|
locals = NULL; /* PyFrame_Fast2Locals() will set. */ |
|
else if (code->co_flags & CO_NEWLOCALS) { |
|
locals = PyDict_New(); |
|
if (locals == NULL) { |
|
Py_DECREF(f); |
|
return NULL; |
|
} |
|
} |
|
else { |
|
if (locals == NULL) |
|
locals = globals; |
|
Py_INCREF(locals); |
|
} |
|
f->f_locals = locals; |
|
f->f_trace = NULL; |
|
f->f_exc_type = f->f_exc_value = f->f_exc_traceback = NULL; |
|
f->f_tstate = tstate; |
|
|
|
f->f_lasti = -1; |
|
f->f_lineno = code->co_firstlineno; |
|
f->f_restricted = (builtins != tstate->interp->builtins); |
|
f->f_iblock = 0; |
|
f->f_nlocals = code->co_nlocals; |
|
f->f_stacksize = code->co_stacksize; |
|
f->f_ncells = ncells; |
|
f->f_nfreevars = nfrees; |
|
|
|
extras = f->f_nlocals + ncells + nfrees; |
|
memset(f->f_localsplus, 0, extras * sizeof(f->f_localsplus[0])); |
|
|
|
f->f_valuestack = f->f_localsplus + extras; |
|
f->f_stacktop = f->f_valuestack; |
|
_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, int nmap, PyObject *dict, PyObject **values, |
|
int deref) |
|
{ |
|
int 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 (PyDict_DelItem(dict, key) != 0) |
|
PyErr_Clear(); |
|
} |
|
else { |
|
if (PyDict_SetItem(dict, key, value) != 0) |
|
PyErr_Clear(); |
|
} |
|
} |
|
} |
|
|
|
static void |
|
dict_to_map(PyObject *map, int nmap, PyObject *dict, PyObject **values, |
|
int deref, int clear) |
|
{ |
|
int j; |
|
for (j = nmap; --j >= 0; ) { |
|
PyObject *key = PyTuple_GET_ITEM(map, j); |
|
PyObject *value = PyDict_GetItem(dict, key); |
|
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; |
|
} |
|
} |
|
} |
|
} |
|
|
|
void |
|
PyFrame_FastToLocals(PyFrameObject *f) |
|
{ |
|
/* Merge fast locals into f->f_locals */ |
|
PyObject *locals, *map; |
|
PyObject **fast; |
|
PyObject *error_type, *error_value, *error_traceback; |
|
int j; |
|
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; |
|
} |
|
} |
|
map = f->f_code->co_varnames; |
|
if (!PyDict_Check(locals) || !PyTuple_Check(map)) |
|
return; |
|
PyErr_Fetch(&error_type, &error_value, &error_traceback); |
|
fast = f->f_localsplus; |
|
j = PyTuple_Size(map); |
|
if (j > f->f_nlocals) |
|
j = f->f_nlocals; |
|
if (f->f_nlocals) |
|
map_to_dict(map, j, locals, fast, 0); |
|
if (f->f_ncells || f->f_nfreevars) { |
|
if (!(PyTuple_Check(f->f_code->co_cellvars) |
|
&& PyTuple_Check(f->f_code->co_freevars))) { |
|
return; |
|
} |
|
map_to_dict(f->f_code->co_cellvars, |
|
PyTuple_GET_SIZE(f->f_code->co_cellvars), |
|
locals, fast + f->f_nlocals, 1); |
|
map_to_dict(f->f_code->co_freevars, |
|
PyTuple_GET_SIZE(f->f_code->co_freevars), |
|
locals, fast + f->f_nlocals + f->f_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; |
|
int j; |
|
if (f == NULL) |
|
return; |
|
locals = f->f_locals; |
|
map = f->f_code->co_varnames; |
|
if (locals == NULL) |
|
return; |
|
if (!PyDict_Check(locals) || !PyTuple_Check(map)) |
|
return; |
|
PyErr_Fetch(&error_type, &error_value, &error_traceback); |
|
fast = f->f_localsplus; |
|
j = PyTuple_Size(map); |
|
if (j > f->f_nlocals) |
|
j = f->f_nlocals; |
|
if (f->f_nlocals) |
|
dict_to_map(f->f_code->co_varnames, j, locals, fast, 0, clear); |
|
if (f->f_ncells || f->f_nfreevars) { |
|
if (!(PyTuple_Check(f->f_code->co_cellvars) |
|
&& PyTuple_Check(f->f_code->co_freevars))) |
|
return; |
|
dict_to_map(f->f_code->co_cellvars, |
|
PyTuple_GET_SIZE(f->f_code->co_cellvars), |
|
locals, fast + f->f_nlocals, 1, clear); |
|
dict_to_map(f->f_code->co_freevars, |
|
PyTuple_GET_SIZE(f->f_code->co_freevars), |
|
locals, fast + f->f_nlocals + f->f_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; |
|
}
|
|
|