Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 1 | /* Frame object implementation */ |
| 2 | |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 3 | #include "Python.h" |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 4 | |
Jeremy Hylton | 3e0055f | 2005-10-20 19:59:25 +0000 | [diff] [blame] | 5 | #include "code.h" |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 6 | #include "frameobject.h" |
| 7 | #include "opcode.h" |
| 8 | #include "structmember.h" |
| 9 | |
Neal Norwitz | 91787cb | 2002-12-18 23:33:35 +0000 | [diff] [blame] | 10 | #undef MIN |
| 11 | #undef MAX |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 12 | #define MIN(a, b) ((a) < (b) ? (a) : (b)) |
| 13 | #define MAX(a, b) ((a) > (b) ? (a) : (b)) |
| 14 | |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 15 | #define OFF(x) offsetof(PyFrameObject, x) |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 16 | |
Guido van Rossum | 6f79937 | 2001-09-20 20:46:19 +0000 | [diff] [blame] | 17 | static PyMemberDef frame_memberlist[] = { |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 18 | {"f_back", T_OBJECT, OFF(f_back), RO}, |
| 19 | {"f_code", T_OBJECT, OFF(f_code), RO}, |
Guido van Rossum | c113482 | 1995-01-10 10:39:16 +0000 | [diff] [blame] | 20 | {"f_builtins", T_OBJECT, OFF(f_builtins),RO}, |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 21 | {"f_globals", T_OBJECT, OFF(f_globals), RO}, |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 22 | {"f_lasti", T_INT, OFF(f_lasti), RO}, |
Guido van Rossum | a027efa | 1997-05-05 20:56:21 +0000 | [diff] [blame] | 23 | {"f_exc_type", T_OBJECT, OFF(f_exc_type)}, |
| 24 | {"f_exc_value", T_OBJECT, OFF(f_exc_value)}, |
| 25 | {"f_exc_traceback", T_OBJECT, OFF(f_exc_traceback)}, |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 26 | {NULL} /* Sentinel */ |
| 27 | }; |
| 28 | |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 29 | static PyObject * |
Tim Peters | 6d6c1a3 | 2001-08-02 04:15:00 +0000 | [diff] [blame] | 30 | frame_getlocals(PyFrameObject *f, void *closure) |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 31 | { |
Tim Peters | 6d6c1a3 | 2001-08-02 04:15:00 +0000 | [diff] [blame] | 32 | PyFrame_FastToLocals(f); |
| 33 | Py_INCREF(f->f_locals); |
| 34 | return f->f_locals; |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 35 | } |
| 36 | |
Michael W. Hudson | dd32a91 | 2002-08-15 14:59:02 +0000 | [diff] [blame] | 37 | static PyObject * |
| 38 | frame_getlineno(PyFrameObject *f, void *closure) |
| 39 | { |
| 40 | int lineno; |
| 41 | |
Michael W. Hudson | 02ff6a9 | 2002-09-11 15:36:32 +0000 | [diff] [blame] | 42 | if (f->f_trace) |
| 43 | lineno = f->f_lineno; |
| 44 | else |
| 45 | lineno = PyCode_Addr2Line(f->f_code, f->f_lasti); |
Michael W. Hudson | dd32a91 | 2002-08-15 14:59:02 +0000 | [diff] [blame] | 46 | |
| 47 | return PyInt_FromLong(lineno); |
| 48 | } |
| 49 | |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 50 | /* Setter for f_lineno - you can set f_lineno from within a trace function in |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 51 | * order to jump to a given line of code, subject to some restrictions. Most |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 52 | * lines are OK to jump to because they don't make any assumptions about the |
| 53 | * state of the stack (obvious because you could remove the line and the code |
| 54 | * would still work without any stack errors), but there are some constructs |
| 55 | * that limit jumping: |
| 56 | * |
| 57 | * o Lines with an 'except' statement on them can't be jumped to, because |
| 58 | * they expect an exception to be on the top of the stack. |
| 59 | * o Lines that live in a 'finally' block can't be jumped from or to, since |
| 60 | * the END_FINALLY expects to clean up the stack after the 'try' block. |
| 61 | * o 'try'/'for'/'while' blocks can't be jumped into because the blockstack |
| 62 | * needs to be set up before their code runs, and for 'for' loops the |
| 63 | * iterator needs to be on the stack. |
| 64 | */ |
| 65 | static int |
| 66 | frame_setlineno(PyFrameObject *f, PyObject* p_new_lineno) |
| 67 | { |
| 68 | int new_lineno = 0; /* The new value of f_lineno */ |
| 69 | int new_lasti = 0; /* The new value of f_lasti */ |
| 70 | int new_iblock = 0; /* The new value of f_iblock */ |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 71 | unsigned char *code = NULL; /* The bytecode for the frame... */ |
Martin v. Löwis | 18e1655 | 2006-02-15 17:27:45 +0000 | [diff] [blame] | 72 | Py_ssize_t code_len = 0; /* ...and its length */ |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 73 | char *lnotab = NULL; /* Iterating over co_lnotab */ |
Martin v. Löwis | 18e1655 | 2006-02-15 17:27:45 +0000 | [diff] [blame] | 74 | Py_ssize_t lnotab_len = 0; /* (ditto) */ |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 75 | int offset = 0; /* (ditto) */ |
| 76 | int line = 0; /* (ditto) */ |
| 77 | int addr = 0; /* (ditto) */ |
| 78 | int min_addr = 0; /* Scanning the SETUPs and POPs */ |
| 79 | int max_addr = 0; /* (ditto) */ |
| 80 | int delta_iblock = 0; /* (ditto) */ |
| 81 | int min_delta_iblock = 0; /* (ditto) */ |
| 82 | int min_iblock = 0; /* (ditto) */ |
| 83 | int f_lasti_setup_addr = 0; /* Policing no-jump-into-finally */ |
| 84 | int new_lasti_setup_addr = 0; /* (ditto) */ |
| 85 | int blockstack[CO_MAXBLOCKS]; /* Walking the 'finally' blocks */ |
| 86 | int in_finally[CO_MAXBLOCKS]; /* (ditto) */ |
| 87 | int blockstack_top = 0; /* (ditto) */ |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 88 | unsigned char setup_op = 0; /* (ditto) */ |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 89 | |
| 90 | /* f_lineno must be an integer. */ |
Guido van Rossum | ddefaf3 | 2007-01-14 03:31:43 +0000 | [diff] [blame] | 91 | if (!PyInt_CheckExact(p_new_lineno)) { |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 92 | PyErr_SetString(PyExc_ValueError, |
| 93 | "lineno must be an integer"); |
| 94 | return -1; |
| 95 | } |
| 96 | |
| 97 | /* You can only do this from within a trace function, not via |
| 98 | * _getframe or similar hackery. */ |
| 99 | if (!f->f_trace) |
| 100 | { |
| 101 | PyErr_Format(PyExc_ValueError, |
| 102 | "f_lineno can only be set by a trace function"); |
| 103 | return -1; |
| 104 | } |
| 105 | |
| 106 | /* Fail if the line comes before the start of the code block. */ |
| 107 | new_lineno = (int) PyInt_AsLong(p_new_lineno); |
| 108 | if (new_lineno < f->f_code->co_firstlineno) { |
| 109 | PyErr_Format(PyExc_ValueError, |
| 110 | "line %d comes before the current code block", |
| 111 | new_lineno); |
| 112 | return -1; |
| 113 | } |
| 114 | |
| 115 | /* Find the bytecode offset for the start of the given line, or the |
| 116 | * first code-owning line after it. */ |
| 117 | PyString_AsStringAndSize(f->f_code->co_lnotab, &lnotab, &lnotab_len); |
| 118 | addr = 0; |
| 119 | line = f->f_code->co_firstlineno; |
| 120 | new_lasti = -1; |
| 121 | for (offset = 0; offset < lnotab_len; offset += 2) { |
| 122 | addr += lnotab[offset]; |
| 123 | line += lnotab[offset+1]; |
| 124 | if (line >= new_lineno) { |
| 125 | new_lasti = addr; |
| 126 | new_lineno = line; |
| 127 | break; |
| 128 | } |
| 129 | } |
| 130 | |
| 131 | /* If we didn't reach the requested line, return an error. */ |
| 132 | if (new_lasti == -1) { |
| 133 | PyErr_Format(PyExc_ValueError, |
| 134 | "line %d comes after the current code block", |
| 135 | new_lineno); |
| 136 | return -1; |
| 137 | } |
| 138 | |
| 139 | /* We're now ready to look at the bytecode. */ |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 140 | PyString_AsStringAndSize(f->f_code->co_code, (char **)&code, &code_len); |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 141 | min_addr = MIN(new_lasti, f->f_lasti); |
| 142 | max_addr = MAX(new_lasti, f->f_lasti); |
| 143 | |
| 144 | /* You can't jump onto a line with an 'except' statement on it - |
| 145 | * they expect to have an exception on the top of the stack, which |
| 146 | * won't be true if you jump to them. They always start with code |
| 147 | * that either pops the exception using POP_TOP (plain 'except:' |
| 148 | * lines do this) or duplicates the exception on the stack using |
| 149 | * DUP_TOP (if there's an exception type specified). See compile.c, |
| 150 | * 'com_try_except' for the full details. There aren't any other |
| 151 | * cases (AFAIK) where a line's code can start with DUP_TOP or |
| 152 | * POP_TOP, but if any ever appear, they'll be subject to the same |
| 153 | * restriction (but with a different error message). */ |
| 154 | if (code[new_lasti] == DUP_TOP || code[new_lasti] == POP_TOP) { |
| 155 | PyErr_SetString(PyExc_ValueError, |
| 156 | "can't jump to 'except' line as there's no exception"); |
| 157 | return -1; |
| 158 | } |
| 159 | |
| 160 | /* You can't jump into or out of a 'finally' block because the 'try' |
| 161 | * block leaves something on the stack for the END_FINALLY to clean |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 162 | * up. So we walk the bytecode, maintaining a simulated blockstack. |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 163 | * When we reach the old or new address and it's in a 'finally' block |
| 164 | * we note the address of the corresponding SETUP_FINALLY. The jump |
| 165 | * is only legal if neither address is in a 'finally' block or |
| 166 | * they're both in the same one. 'blockstack' is a stack of the |
| 167 | * bytecode addresses of the SETUP_X opcodes, and 'in_finally' tracks |
| 168 | * whether we're in a 'finally' block at each blockstack level. */ |
| 169 | f_lasti_setup_addr = -1; |
| 170 | new_lasti_setup_addr = -1; |
| 171 | memset(blockstack, '\0', sizeof(blockstack)); |
| 172 | memset(in_finally, '\0', sizeof(in_finally)); |
| 173 | blockstack_top = 0; |
| 174 | for (addr = 0; addr < code_len; addr++) { |
| 175 | unsigned char op = code[addr]; |
| 176 | switch (op) { |
| 177 | case SETUP_LOOP: |
| 178 | case SETUP_EXCEPT: |
| 179 | case SETUP_FINALLY: |
| 180 | blockstack[blockstack_top++] = addr; |
| 181 | in_finally[blockstack_top-1] = 0; |
| 182 | break; |
| 183 | |
| 184 | case POP_BLOCK: |
Neal Norwitz | ee65e22 | 2002-12-19 18:16:57 +0000 | [diff] [blame] | 185 | assert(blockstack_top > 0); |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 186 | setup_op = code[blockstack[blockstack_top-1]]; |
| 187 | if (setup_op == SETUP_FINALLY) { |
| 188 | in_finally[blockstack_top-1] = 1; |
| 189 | } |
| 190 | else { |
| 191 | blockstack_top--; |
| 192 | } |
| 193 | break; |
| 194 | |
| 195 | case END_FINALLY: |
| 196 | /* Ignore END_FINALLYs for SETUP_EXCEPTs - they exist |
| 197 | * in the bytecode but don't correspond to an actual |
Neal Norwitz | ee65e22 | 2002-12-19 18:16:57 +0000 | [diff] [blame] | 198 | * 'finally' block. (If blockstack_top is 0, we must |
| 199 | * be seeing such an END_FINALLY.) */ |
| 200 | if (blockstack_top > 0) { |
| 201 | setup_op = code[blockstack[blockstack_top-1]]; |
| 202 | if (setup_op == SETUP_FINALLY) { |
| 203 | blockstack_top--; |
| 204 | } |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 205 | } |
| 206 | break; |
| 207 | } |
| 208 | |
| 209 | /* For the addresses we're interested in, see whether they're |
| 210 | * within a 'finally' block and if so, remember the address |
| 211 | * of the SETUP_FINALLY. */ |
| 212 | if (addr == new_lasti || addr == f->f_lasti) { |
| 213 | int i = 0; |
| 214 | int setup_addr = -1; |
| 215 | for (i = blockstack_top-1; i >= 0; i--) { |
| 216 | if (in_finally[i]) { |
| 217 | setup_addr = blockstack[i]; |
| 218 | break; |
| 219 | } |
| 220 | } |
| 221 | |
| 222 | if (setup_addr != -1) { |
| 223 | if (addr == new_lasti) { |
| 224 | new_lasti_setup_addr = setup_addr; |
| 225 | } |
| 226 | |
| 227 | if (addr == f->f_lasti) { |
| 228 | f_lasti_setup_addr = setup_addr; |
| 229 | } |
| 230 | } |
| 231 | } |
| 232 | |
| 233 | if (op >= HAVE_ARGUMENT) { |
| 234 | addr += 2; |
| 235 | } |
| 236 | } |
| 237 | |
Neal Norwitz | ee65e22 | 2002-12-19 18:16:57 +0000 | [diff] [blame] | 238 | /* Verify that the blockstack tracking code didn't get lost. */ |
| 239 | assert(blockstack_top == 0); |
| 240 | |
| 241 | /* After all that, are we jumping into / out of a 'finally' block? */ |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 242 | if (new_lasti_setup_addr != f_lasti_setup_addr) { |
| 243 | PyErr_SetString(PyExc_ValueError, |
| 244 | "can't jump into or out of a 'finally' block"); |
| 245 | return -1; |
| 246 | } |
| 247 | |
| 248 | |
| 249 | /* Police block-jumping (you can't jump into the middle of a block) |
| 250 | * and ensure that the blockstack finishes up in a sensible state (by |
| 251 | * popping any blocks we're jumping out of). We look at all the |
| 252 | * blockstack operations between the current position and the new |
| 253 | * one, and keep track of how many blocks we drop out of on the way. |
| 254 | * By also keeping track of the lowest blockstack position we see, we |
| 255 | * can tell whether the jump goes into any blocks without coming out |
| 256 | * again - in that case we raise an exception below. */ |
| 257 | delta_iblock = 0; |
| 258 | for (addr = min_addr; addr < max_addr; addr++) { |
| 259 | unsigned char op = code[addr]; |
| 260 | switch (op) { |
| 261 | case SETUP_LOOP: |
| 262 | case SETUP_EXCEPT: |
| 263 | case SETUP_FINALLY: |
| 264 | delta_iblock++; |
| 265 | break; |
| 266 | |
| 267 | case POP_BLOCK: |
| 268 | delta_iblock--; |
| 269 | break; |
| 270 | } |
| 271 | |
| 272 | min_delta_iblock = MIN(min_delta_iblock, delta_iblock); |
| 273 | |
| 274 | if (op >= HAVE_ARGUMENT) { |
| 275 | addr += 2; |
| 276 | } |
| 277 | } |
| 278 | |
| 279 | /* Derive the absolute iblock values from the deltas. */ |
| 280 | min_iblock = f->f_iblock + min_delta_iblock; |
| 281 | if (new_lasti > f->f_lasti) { |
| 282 | /* Forwards jump. */ |
| 283 | new_iblock = f->f_iblock + delta_iblock; |
| 284 | } |
| 285 | else { |
| 286 | /* Backwards jump. */ |
| 287 | new_iblock = f->f_iblock - delta_iblock; |
| 288 | } |
| 289 | |
| 290 | /* Are we jumping into a block? */ |
| 291 | if (new_iblock > min_iblock) { |
| 292 | PyErr_SetString(PyExc_ValueError, |
| 293 | "can't jump into the middle of a block"); |
| 294 | return -1; |
| 295 | } |
| 296 | |
| 297 | /* Pop any blocks that we're jumping out of. */ |
| 298 | while (f->f_iblock > new_iblock) { |
| 299 | PyTryBlock *b = &f->f_blockstack[--f->f_iblock]; |
| 300 | while ((f->f_stacktop - f->f_valuestack) > b->b_level) { |
| 301 | PyObject *v = (*--f->f_stacktop); |
| 302 | Py_DECREF(v); |
| 303 | } |
| 304 | } |
| 305 | |
| 306 | /* Finally set the new f_lineno and f_lasti and return OK. */ |
| 307 | f->f_lineno = new_lineno; |
| 308 | f->f_lasti = new_lasti; |
| 309 | return 0; |
| 310 | } |
| 311 | |
Michael W. Hudson | 02ff6a9 | 2002-09-11 15:36:32 +0000 | [diff] [blame] | 312 | static PyObject * |
| 313 | frame_gettrace(PyFrameObject *f, void *closure) |
| 314 | { |
| 315 | PyObject* trace = f->f_trace; |
| 316 | |
| 317 | if (trace == NULL) |
| 318 | trace = Py_None; |
| 319 | |
| 320 | Py_INCREF(trace); |
| 321 | |
| 322 | return trace; |
| 323 | } |
| 324 | |
| 325 | static int |
| 326 | frame_settrace(PyFrameObject *f, PyObject* v, void *closure) |
| 327 | { |
| 328 | /* We rely on f_lineno being accurate when f_trace is set. */ |
| 329 | |
| 330 | PyObject* old_value = f->f_trace; |
| 331 | |
| 332 | Py_XINCREF(v); |
| 333 | f->f_trace = v; |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 334 | |
Michael W. Hudson | 02ff6a9 | 2002-09-11 15:36:32 +0000 | [diff] [blame] | 335 | if (v != NULL) |
| 336 | f->f_lineno = PyCode_Addr2Line(f->f_code, f->f_lasti); |
| 337 | |
| 338 | Py_XDECREF(old_value); |
| 339 | |
| 340 | return 0; |
| 341 | } |
| 342 | |
Thomas Wouters | 0e3f591 | 2006-08-11 14:57:12 +0000 | [diff] [blame] | 343 | |
Guido van Rossum | 32d34c8 | 2001-09-20 21:45:26 +0000 | [diff] [blame] | 344 | static PyGetSetDef frame_getsetlist[] = { |
Tim Peters | 6d6c1a3 | 2001-08-02 04:15:00 +0000 | [diff] [blame] | 345 | {"f_locals", (getter)frame_getlocals, NULL, NULL}, |
Michael W. Hudson | cfd3884 | 2002-12-17 16:15:34 +0000 | [diff] [blame] | 346 | {"f_lineno", (getter)frame_getlineno, |
| 347 | (setter)frame_setlineno, NULL}, |
Michael W. Hudson | 02ff6a9 | 2002-09-11 15:36:32 +0000 | [diff] [blame] | 348 | {"f_trace", (getter)frame_gettrace, (setter)frame_settrace, NULL}, |
Tim Peters | 6d6c1a3 | 2001-08-02 04:15:00 +0000 | [diff] [blame] | 349 | {0} |
| 350 | }; |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 351 | |
Guido van Rossum | a9e7dc1 | 1992-10-18 18:53:57 +0000 | [diff] [blame] | 352 | /* Stack frames are allocated and deallocated at a considerable rate. |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 353 | In an attempt to improve the speed of function calls, we: |
| 354 | |
| 355 | 1. Hold a single "zombie" frame on each code object. This retains |
| 356 | the allocated and initialised frame object from an invocation of |
| 357 | the code object. The zombie is reanimated the next time we need a |
| 358 | frame object for that code object. Doing this saves the malloc/ |
| 359 | realloc required when using a free_list frame that isn't the |
| 360 | correct size. It also saves some field initialisation. |
| 361 | |
| 362 | In zombie mode, no field of PyFrameObject holds a reference, but |
| 363 | the following fields are still valid: |
| 364 | |
| 365 | * ob_type, ob_size, f_code, f_valuestack; |
| 366 | |
| 367 | * f_locals, f_trace, |
| 368 | f_exc_type, f_exc_value, f_exc_traceback are NULL; |
| 369 | |
| 370 | * f_localsplus does not require re-allocation and |
| 371 | the local variables in f_localsplus are NULL. |
| 372 | |
| 373 | 2. We also maintain a separate free list of stack frames (just like |
| 374 | integers are allocated in a special way -- see intobject.c). When |
| 375 | a stack frame is on the free list, only the following members have |
| 376 | a meaning: |
Guido van Rossum | a9e7dc1 | 1992-10-18 18:53:57 +0000 | [diff] [blame] | 377 | ob_type == &Frametype |
| 378 | f_back next item on free list, or NULL |
Guido van Rossum | f3e85a0 | 1997-01-20 04:20:52 +0000 | [diff] [blame] | 379 | f_stacksize size of value stack |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 380 | ob_size size of localsplus |
Guido van Rossum | a9e7dc1 | 1992-10-18 18:53:57 +0000 | [diff] [blame] | 381 | Note that the value and block stacks are preserved -- this can save |
| 382 | another malloc() call or two (and two free() calls as well!). |
| 383 | Also note that, unlike for integers, each frame object is a |
| 384 | malloc'ed object in its own right -- it is only the actual calls to |
| 385 | malloc() that we are trying to save here, not the administration. |
| 386 | After all, while a typical program may make millions of calls, a |
| 387 | call depth of more than 20 or 30 is probably already exceptional |
| 388 | unless the program contains run-away recursion. I hope. |
Tim Peters | b7ba743 | 2002-04-13 05:21:47 +0000 | [diff] [blame] | 389 | |
| 390 | Later, MAXFREELIST was added to bound the # of frames saved on |
| 391 | free_list. Else programs creating lots of cyclic trash involving |
| 392 | frames could provoke free_list into growing without bound. |
Guido van Rossum | a9e7dc1 | 1992-10-18 18:53:57 +0000 | [diff] [blame] | 393 | */ |
| 394 | |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 395 | static PyFrameObject *free_list = NULL; |
Tim Peters | b7ba743 | 2002-04-13 05:21:47 +0000 | [diff] [blame] | 396 | static int numfree = 0; /* number of frames currently in free_list */ |
| 397 | #define MAXFREELIST 200 /* max value for numfree */ |
Guido van Rossum | a9e7dc1 | 1992-10-18 18:53:57 +0000 | [diff] [blame] | 398 | |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 399 | static void |
Fred Drake | 1b190b4 | 2000-07-09 05:40:56 +0000 | [diff] [blame] | 400 | frame_dealloc(PyFrameObject *f) |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 401 | { |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 402 | PyObject **p, **valuestack; |
| 403 | PyCodeObject *co; |
Guido van Rossum | 7582bfb | 1997-02-14 16:27:29 +0000 | [diff] [blame] | 404 | |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 405 | PyObject_GC_UnTrack(f); |
Guido van Rossum | d724b23 | 2000-03-13 16:01:29 +0000 | [diff] [blame] | 406 | Py_TRASHCAN_SAFE_BEGIN(f) |
Guido van Rossum | 7582bfb | 1997-02-14 16:27:29 +0000 | [diff] [blame] | 407 | /* Kill all local variables */ |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 408 | valuestack = f->f_valuestack; |
| 409 | for (p = f->f_localsplus; p < valuestack; p++) |
| 410 | Py_CLEAR(*p); |
Guido van Rossum | 7582bfb | 1997-02-14 16:27:29 +0000 | [diff] [blame] | 411 | |
Tim Peters | 5ca576e | 2001-06-18 22:08:13 +0000 | [diff] [blame] | 412 | /* Free stack */ |
Tim Peters | 8c96369 | 2001-06-23 05:26:56 +0000 | [diff] [blame] | 413 | if (f->f_stacktop != NULL) { |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 414 | for (p = valuestack; p < f->f_stacktop; p++) |
Tim Peters | 8c96369 | 2001-06-23 05:26:56 +0000 | [diff] [blame] | 415 | Py_XDECREF(*p); |
Tim Peters | 5ca576e | 2001-06-18 22:08:13 +0000 | [diff] [blame] | 416 | } |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 417 | |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 418 | Py_XDECREF(f->f_back); |
Neal Norwitz | c91ed40 | 2002-12-30 22:29:22 +0000 | [diff] [blame] | 419 | Py_DECREF(f->f_builtins); |
| 420 | Py_DECREF(f->f_globals); |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 421 | Py_CLEAR(f->f_locals); |
| 422 | Py_CLEAR(f->f_trace); |
| 423 | Py_CLEAR(f->f_exc_type); |
| 424 | Py_CLEAR(f->f_exc_value); |
| 425 | Py_CLEAR(f->f_exc_traceback); |
| 426 | |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 427 | co = f->f_code; |
| 428 | if (co->co_zombieframe == NULL) |
| 429 | co->co_zombieframe = f; |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 430 | else if (numfree < MAXFREELIST) { |
Tim Peters | b7ba743 | 2002-04-13 05:21:47 +0000 | [diff] [blame] | 431 | ++numfree; |
| 432 | f->f_back = free_list; |
| 433 | free_list = f; |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 434 | } |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 435 | else |
Tim Peters | b7ba743 | 2002-04-13 05:21:47 +0000 | [diff] [blame] | 436 | PyObject_GC_Del(f); |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 437 | |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 438 | Py_DECREF(co); |
Guido van Rossum | d724b23 | 2000-03-13 16:01:29 +0000 | [diff] [blame] | 439 | Py_TRASHCAN_SAFE_END(f) |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 440 | } |
| 441 | |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 442 | static int |
| 443 | frame_traverse(PyFrameObject *f, visitproc visit, void *arg) |
| 444 | { |
| 445 | PyObject **fastlocals, **p; |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 446 | int i, slots; |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 447 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 448 | Py_VISIT(f->f_back); |
| 449 | Py_VISIT(f->f_code); |
| 450 | Py_VISIT(f->f_builtins); |
| 451 | Py_VISIT(f->f_globals); |
| 452 | Py_VISIT(f->f_locals); |
| 453 | Py_VISIT(f->f_trace); |
| 454 | Py_VISIT(f->f_exc_type); |
| 455 | Py_VISIT(f->f_exc_value); |
| 456 | Py_VISIT(f->f_exc_traceback); |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 457 | |
| 458 | /* locals */ |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 459 | slots = f->f_code->co_nlocals + PyTuple_GET_SIZE(f->f_code->co_cellvars) + PyTuple_GET_SIZE(f->f_code->co_freevars); |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 460 | fastlocals = f->f_localsplus; |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 461 | for (i = slots; --i >= 0; ++fastlocals) |
| 462 | Py_VISIT(*fastlocals); |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 463 | |
| 464 | /* stack */ |
| 465 | if (f->f_stacktop != NULL) { |
| 466 | for (p = f->f_valuestack; p < f->f_stacktop; p++) |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 467 | Py_VISIT(*p); |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 468 | } |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 469 | return 0; |
| 470 | } |
| 471 | |
| 472 | static void |
| 473 | frame_clear(PyFrameObject *f) |
| 474 | { |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 475 | PyObject **fastlocals, **p, **oldtop; |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 476 | int i, slots; |
| 477 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 478 | /* Before anything else, make sure that this frame is clearly marked |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 479 | * as being defunct! Else, e.g., a generator reachable from this |
| 480 | * frame may also point to this frame, believe itself to still be |
| 481 | * active, and try cleaning up this frame again. |
| 482 | */ |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 483 | oldtop = f->f_stacktop; |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 484 | f->f_stacktop = NULL; |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 485 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 486 | Py_CLEAR(f->f_exc_type); |
| 487 | Py_CLEAR(f->f_exc_value); |
| 488 | Py_CLEAR(f->f_exc_traceback); |
| 489 | Py_CLEAR(f->f_trace); |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 490 | |
| 491 | /* locals */ |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 492 | slots = f->f_code->co_nlocals + PyTuple_GET_SIZE(f->f_code->co_cellvars) + PyTuple_GET_SIZE(f->f_code->co_freevars); |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 493 | fastlocals = f->f_localsplus; |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 494 | for (i = slots; --i >= 0; ++fastlocals) |
| 495 | Py_CLEAR(*fastlocals); |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 496 | |
| 497 | /* stack */ |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 498 | if (oldtop != NULL) { |
| 499 | for (p = f->f_valuestack; p < oldtop; p++) |
| 500 | Py_CLEAR(*p); |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 501 | } |
| 502 | } |
| 503 | |
| 504 | |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 505 | PyTypeObject PyFrame_Type = { |
| 506 | PyObject_HEAD_INIT(&PyType_Type) |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 507 | 0, |
| 508 | "frame", |
Neil Schemenauer | 4f4817f | 2001-08-29 23:52:17 +0000 | [diff] [blame] | 509 | sizeof(PyFrameObject), |
| 510 | sizeof(PyObject *), |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 511 | (destructor)frame_dealloc, /* tp_dealloc */ |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 512 | 0, /* tp_print */ |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 513 | 0, /* tp_getattr */ |
| 514 | 0, /* tp_setattr */ |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 515 | 0, /* tp_compare */ |
| 516 | 0, /* tp_repr */ |
| 517 | 0, /* tp_as_number */ |
| 518 | 0, /* tp_as_sequence */ |
| 519 | 0, /* tp_as_mapping */ |
| 520 | 0, /* tp_hash */ |
| 521 | 0, /* tp_call */ |
| 522 | 0, /* tp_str */ |
Tim Peters | 6d6c1a3 | 2001-08-02 04:15:00 +0000 | [diff] [blame] | 523 | PyObject_GenericGetAttr, /* tp_getattro */ |
| 524 | PyObject_GenericSetAttr, /* tp_setattro */ |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 525 | 0, /* tp_as_buffer */ |
Neil Schemenauer | 4f4817f | 2001-08-29 23:52:17 +0000 | [diff] [blame] | 526 | Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */ |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 527 | 0, /* tp_doc */ |
| 528 | (traverseproc)frame_traverse, /* tp_traverse */ |
Neil Schemenauer | 19cd292 | 2001-07-12 13:27:11 +0000 | [diff] [blame] | 529 | (inquiry)frame_clear, /* tp_clear */ |
Tim Peters | 6d6c1a3 | 2001-08-02 04:15:00 +0000 | [diff] [blame] | 530 | 0, /* tp_richcompare */ |
| 531 | 0, /* tp_weaklistoffset */ |
| 532 | 0, /* tp_iter */ |
| 533 | 0, /* tp_iternext */ |
| 534 | 0, /* tp_methods */ |
| 535 | frame_memberlist, /* tp_members */ |
| 536 | frame_getsetlist, /* tp_getset */ |
| 537 | 0, /* tp_base */ |
| 538 | 0, /* tp_dict */ |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 539 | }; |
| 540 | |
Neal Norwitz | c91ed40 | 2002-12-30 22:29:22 +0000 | [diff] [blame] | 541 | static PyObject *builtin_object; |
| 542 | |
Neal Norwitz | b2501f4 | 2002-12-31 03:42:13 +0000 | [diff] [blame] | 543 | int _PyFrame_Init() |
Neal Norwitz | c91ed40 | 2002-12-30 22:29:22 +0000 | [diff] [blame] | 544 | { |
| 545 | builtin_object = PyString_InternFromString("__builtins__"); |
| 546 | return (builtin_object != NULL); |
| 547 | } |
| 548 | |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 549 | PyFrameObject * |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 550 | PyFrame_New(PyThreadState *tstate, PyCodeObject *code, PyObject *globals, |
Jeremy Hylton | 30c9f39 | 2001-03-13 01:58:22 +0000 | [diff] [blame] | 551 | PyObject *locals) |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 552 | { |
Guido van Rossum | a027efa | 1997-05-05 20:56:21 +0000 | [diff] [blame] | 553 | PyFrameObject *back = tstate->frame; |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 554 | PyFrameObject *f; |
| 555 | PyObject *builtins; |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 556 | Py_ssize_t i; |
Guido van Rossum | f3e85a0 | 1997-01-20 04:20:52 +0000 | [diff] [blame] | 557 | |
Michael W. Hudson | 69734a5 | 2002-08-19 16:54:08 +0000 | [diff] [blame] | 558 | #ifdef Py_DEBUG |
| 559 | if (code == NULL || globals == NULL || !PyDict_Check(globals) || |
Raymond Hettinger | 214b1c3 | 2004-07-02 06:41:07 +0000 | [diff] [blame] | 560 | (locals != NULL && !PyMapping_Check(locals))) { |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 561 | PyErr_BadInternalCall(); |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 562 | return NULL; |
| 563 | } |
Michael W. Hudson | 69734a5 | 2002-08-19 16:54:08 +0000 | [diff] [blame] | 564 | #endif |
Guido van Rossum | bde6ff7 | 1998-02-19 20:48:26 +0000 | [diff] [blame] | 565 | if (back == NULL || back->f_globals != globals) { |
| 566 | builtins = PyDict_GetItem(globals, builtin_object); |
Jeremy Hylton | bd5cbf8 | 2003-02-05 22:39:29 +0000 | [diff] [blame] | 567 | if (builtins) { |
| 568 | if (PyModule_Check(builtins)) { |
| 569 | builtins = PyModule_GetDict(builtins); |
| 570 | assert(!builtins || PyDict_Check(builtins)); |
| 571 | } |
| 572 | else if (!PyDict_Check(builtins)) |
| 573 | builtins = NULL; |
| 574 | } |
| 575 | if (builtins == NULL) { |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 576 | /* No builtins! Make up a minimal one |
Jeremy Hylton | bd5cbf8 | 2003-02-05 22:39:29 +0000 | [diff] [blame] | 577 | Give them 'None', at least. */ |
| 578 | builtins = PyDict_New(); |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 579 | if (builtins == NULL || |
Jeremy Hylton | bd5cbf8 | 2003-02-05 22:39:29 +0000 | [diff] [blame] | 580 | PyDict_SetItemString( |
| 581 | builtins, "None", Py_None) < 0) |
| 582 | return NULL; |
| 583 | } |
| 584 | else |
| 585 | Py_INCREF(builtins); |
| 586 | |
Guido van Rossum | bde6ff7 | 1998-02-19 20:48:26 +0000 | [diff] [blame] | 587 | } |
| 588 | else { |
| 589 | /* If we share the globals, we share the builtins. |
| 590 | Save a lookup and a call. */ |
| 591 | builtins = back->f_builtins; |
Jeremy Hylton | bd5cbf8 | 2003-02-05 22:39:29 +0000 | [diff] [blame] | 592 | assert(builtins != NULL && PyDict_Check(builtins)); |
| 593 | Py_INCREF(builtins); |
Guido van Rossum | bde6ff7 | 1998-02-19 20:48:26 +0000 | [diff] [blame] | 594 | } |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 595 | if (code->co_zombieframe != NULL) { |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 596 | f = code->co_zombieframe; |
| 597 | code->co_zombieframe = NULL; |
| 598 | _Py_NewReference((PyObject *)f); |
| 599 | assert(f->f_code == code); |
Guido van Rossum | a9e7dc1 | 1992-10-18 18:53:57 +0000 | [diff] [blame] | 600 | } |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 601 | else { |
| 602 | Py_ssize_t extras, ncells, nfrees; |
| 603 | ncells = PyTuple_GET_SIZE(code->co_cellvars); |
| 604 | nfrees = PyTuple_GET_SIZE(code->co_freevars); |
| 605 | extras = code->co_stacksize + code->co_nlocals + ncells + |
| 606 | nfrees; |
| 607 | if (free_list == NULL) { |
| 608 | f = PyObject_GC_NewVar(PyFrameObject, &PyFrame_Type, |
| 609 | extras); |
| 610 | if (f == NULL) { |
| 611 | Py_DECREF(builtins); |
| 612 | return NULL; |
| 613 | } |
| 614 | } |
| 615 | else { |
| 616 | assert(numfree > 0); |
| 617 | --numfree; |
| 618 | f = free_list; |
| 619 | free_list = free_list->f_back; |
| 620 | if (f->ob_size < extras) { |
| 621 | f = PyObject_GC_Resize(PyFrameObject, f, extras); |
| 622 | if (f == NULL) { |
| 623 | Py_DECREF(builtins); |
| 624 | return NULL; |
| 625 | } |
| 626 | } |
| 627 | _Py_NewReference((PyObject *)f); |
| 628 | } |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 629 | |
| 630 | f->f_code = code; |
| 631 | extras = code->co_nlocals + ncells + nfrees; |
| 632 | f->f_valuestack = f->f_localsplus + extras; |
| 633 | for (i=0; i<extras; i++) |
| 634 | f->f_localsplus[i] = NULL; |
| 635 | f->f_locals = NULL; |
| 636 | f->f_trace = NULL; |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 637 | f->f_exc_type = f->f_exc_value = f->f_exc_traceback = NULL; |
Guido van Rossum | a9e7dc1 | 1992-10-18 18:53:57 +0000 | [diff] [blame] | 638 | } |
Thomas Wouters | 0e3f591 | 2006-08-11 14:57:12 +0000 | [diff] [blame] | 639 | f->f_stacktop = f->f_valuestack; |
Guido van Rossum | 404b95d | 1997-08-05 02:09:46 +0000 | [diff] [blame] | 640 | f->f_builtins = builtins; |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 641 | Py_XINCREF(back); |
Guido van Rossum | 2271bf7 | 1995-07-18 14:30:34 +0000 | [diff] [blame] | 642 | f->f_back = back; |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 643 | Py_INCREF(code); |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 644 | Py_INCREF(globals); |
Guido van Rossum | 2271bf7 | 1995-07-18 14:30:34 +0000 | [diff] [blame] | 645 | f->f_globals = globals; |
Jeremy Hylton | bd5cbf8 | 2003-02-05 22:39:29 +0000 | [diff] [blame] | 646 | /* Most functions have CO_NEWLOCALS and CO_OPTIMIZED set. */ |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 647 | if ((code->co_flags & (CO_NEWLOCALS | CO_OPTIMIZED)) == |
Jeremy Hylton | bd5cbf8 | 2003-02-05 22:39:29 +0000 | [diff] [blame] | 648 | (CO_NEWLOCALS | CO_OPTIMIZED)) |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 649 | ; /* f_locals = NULL; will be set by PyFrame_FastToLocals() */ |
Jeremy Hylton | bd5cbf8 | 2003-02-05 22:39:29 +0000 | [diff] [blame] | 650 | else if (code->co_flags & CO_NEWLOCALS) { |
| 651 | locals = PyDict_New(); |
| 652 | if (locals == NULL) { |
| 653 | Py_DECREF(f); |
| 654 | return NULL; |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 655 | } |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 656 | f->f_locals = locals; |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 657 | } |
Guido van Rossum | 2271bf7 | 1995-07-18 14:30:34 +0000 | [diff] [blame] | 658 | else { |
| 659 | if (locals == NULL) |
| 660 | locals = globals; |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 661 | Py_INCREF(locals); |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 662 | f->f_locals = locals; |
Guido van Rossum | 2271bf7 | 1995-07-18 14:30:34 +0000 | [diff] [blame] | 663 | } |
Guido van Rossum | eb46d67 | 1997-08-02 02:59:08 +0000 | [diff] [blame] | 664 | f->f_tstate = tstate; |
Guido van Rossum | f3e85a0 | 1997-01-20 04:20:52 +0000 | [diff] [blame] | 665 | |
Michael W. Hudson | dd32a91 | 2002-08-15 14:59:02 +0000 | [diff] [blame] | 666 | f->f_lasti = -1; |
Guido van Rossum | 747596a | 1997-01-24 04:00:21 +0000 | [diff] [blame] | 667 | f->f_lineno = code->co_firstlineno; |
Guido van Rossum | f3e85a0 | 1997-01-20 04:20:52 +0000 | [diff] [blame] | 668 | f->f_iblock = 0; |
Guido van Rossum | f3e85a0 | 1997-01-20 04:20:52 +0000 | [diff] [blame] | 669 | |
Neil Schemenauer | 4f4817f | 2001-08-29 23:52:17 +0000 | [diff] [blame] | 670 | _PyObject_GC_TRACK(f); |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 671 | return f; |
| 672 | } |
| 673 | |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 674 | /* Block management */ |
| 675 | |
| 676 | void |
Fred Drake | 1b190b4 | 2000-07-09 05:40:56 +0000 | [diff] [blame] | 677 | PyFrame_BlockSetup(PyFrameObject *f, int type, int handler, int level) |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 678 | { |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 679 | PyTryBlock *b; |
Guido van Rossum | f3e85a0 | 1997-01-20 04:20:52 +0000 | [diff] [blame] | 680 | if (f->f_iblock >= CO_MAXBLOCKS) |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 681 | Py_FatalError("XXX block stack overflow"); |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 682 | b = &f->f_blockstack[f->f_iblock++]; |
| 683 | b->b_type = type; |
| 684 | b->b_level = level; |
| 685 | b->b_handler = handler; |
| 686 | } |
| 687 | |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 688 | PyTryBlock * |
Fred Drake | 1b190b4 | 2000-07-09 05:40:56 +0000 | [diff] [blame] | 689 | PyFrame_BlockPop(PyFrameObject *f) |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 690 | { |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 691 | PyTryBlock *b; |
Guido van Rossum | d7047b3 | 1995-01-02 19:07:15 +0000 | [diff] [blame] | 692 | if (f->f_iblock <= 0) |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 693 | Py_FatalError("XXX block stack underflow"); |
Guido van Rossum | 3f5da24 | 1990-12-20 15:06:42 +0000 | [diff] [blame] | 694 | b = &f->f_blockstack[--f->f_iblock]; |
| 695 | return b; |
| 696 | } |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 697 | |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 698 | /* Convert between "fast" version of locals and dictionary version. |
| 699 | |
| 700 | map and values are input arguments. map is a tuple of strings. |
| 701 | values is an array of PyObject*. At index i, map[i] is the name of |
| 702 | the variable with value values[i]. The function copies the first |
| 703 | nmap variable from map/values into dict. If values[i] is NULL, |
| 704 | the variable is deleted from dict. |
| 705 | |
| 706 | If deref is true, then the values being copied are cell variables |
| 707 | and the value is extracted from the cell variable before being put |
| 708 | in dict. |
| 709 | |
| 710 | Exceptions raised while modifying the dict are silently ignored, |
| 711 | because there is no good way to report them. |
| 712 | */ |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 713 | |
Guido van Rossum | f68d8e5 | 2001-04-14 17:55:09 +0000 | [diff] [blame] | 714 | static void |
Martin v. Löwis | 18e1655 | 2006-02-15 17:27:45 +0000 | [diff] [blame] | 715 | map_to_dict(PyObject *map, Py_ssize_t nmap, PyObject *dict, PyObject **values, |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 716 | int deref) |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 717 | { |
Martin v. Löwis | 18e1655 | 2006-02-15 17:27:45 +0000 | [diff] [blame] | 718 | Py_ssize_t j; |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 719 | assert(PyTuple_Check(map)); |
| 720 | assert(PyDict_Check(dict)); |
| 721 | assert(PyTuple_Size(map) >= nmap); |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 722 | for (j = nmap; --j >= 0; ) { |
Jeremy Hylton | 1a48ca8 | 2001-12-06 15:48:16 +0000 | [diff] [blame] | 723 | PyObject *key = PyTuple_GET_ITEM(map, j); |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 724 | PyObject *value = values[j]; |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 725 | assert(PyString_Check(key)); |
| 726 | if (deref) { |
| 727 | assert(PyCell_Check(value)); |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 728 | value = PyCell_GET(value); |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 729 | } |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 730 | if (value == NULL) { |
Raymond Hettinger | 214b1c3 | 2004-07-02 06:41:07 +0000 | [diff] [blame] | 731 | if (PyObject_DelItem(dict, key) != 0) |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 732 | PyErr_Clear(); |
| 733 | } |
| 734 | else { |
Raymond Hettinger | 214b1c3 | 2004-07-02 06:41:07 +0000 | [diff] [blame] | 735 | if (PyObject_SetItem(dict, key, value) != 0) |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 736 | PyErr_Clear(); |
| 737 | } |
| 738 | } |
| 739 | } |
| 740 | |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 741 | /* Copy values from the "locals" dict into the fast locals. |
| 742 | |
| 743 | dict is an input argument containing string keys representing |
| 744 | variables names and arbitrary PyObject* as values. |
| 745 | |
| 746 | map and values are input arguments. map is a tuple of strings. |
| 747 | values is an array of PyObject*. At index i, map[i] is the name of |
| 748 | the variable with value values[i]. The function copies the first |
| 749 | nmap variable from map/values into dict. If values[i] is NULL, |
| 750 | the variable is deleted from dict. |
| 751 | |
| 752 | If deref is true, then the values being copied are cell variables |
| 753 | and the value is extracted from the cell variable before being put |
| 754 | in dict. If clear is true, then variables in map but not in dict |
| 755 | are set to NULL in map; if clear is false, variables missing in |
| 756 | dict are ignored. |
| 757 | |
| 758 | Exceptions raised while modifying the dict are silently ignored, |
| 759 | because there is no good way to report them. |
| 760 | */ |
| 761 | |
Guido van Rossum | 6b356e7 | 2001-04-14 17:55:41 +0000 | [diff] [blame] | 762 | static void |
Martin v. Löwis | 18e1655 | 2006-02-15 17:27:45 +0000 | [diff] [blame] | 763 | dict_to_map(PyObject *map, Py_ssize_t nmap, PyObject *dict, PyObject **values, |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 764 | int deref, int clear) |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 765 | { |
Martin v. Löwis | 18e1655 | 2006-02-15 17:27:45 +0000 | [diff] [blame] | 766 | Py_ssize_t j; |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 767 | assert(PyTuple_Check(map)); |
| 768 | assert(PyDict_Check(dict)); |
| 769 | assert(PyTuple_Size(map) >= nmap); |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 770 | for (j = nmap; --j >= 0; ) { |
Jeremy Hylton | 1a48ca8 | 2001-12-06 15:48:16 +0000 | [diff] [blame] | 771 | PyObject *key = PyTuple_GET_ITEM(map, j); |
Raymond Hettinger | 214b1c3 | 2004-07-02 06:41:07 +0000 | [diff] [blame] | 772 | PyObject *value = PyObject_GetItem(dict, key); |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 773 | assert(PyString_Check(key)); |
| 774 | /* We only care about NULLs if clear is true. */ |
| 775 | if (value == NULL) { |
Raymond Hettinger | 214b1c3 | 2004-07-02 06:41:07 +0000 | [diff] [blame] | 776 | PyErr_Clear(); |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 777 | if (!clear) |
| 778 | continue; |
| 779 | } |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 780 | if (deref) { |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 781 | assert(PyCell_Check(values[j])); |
| 782 | if (PyCell_GET(values[j]) != value) { |
| 783 | if (PyCell_Set(values[j], value) < 0) |
| 784 | PyErr_Clear(); |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 785 | } |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 786 | } else if (values[j] != value) { |
| 787 | Py_XINCREF(value); |
| 788 | Py_XDECREF(values[j]); |
| 789 | values[j] = value; |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 790 | } |
Raymond Hettinger | 214b1c3 | 2004-07-02 06:41:07 +0000 | [diff] [blame] | 791 | Py_XDECREF(value); |
Jeremy Hylton | 220ae7c | 2001-03-21 16:43:47 +0000 | [diff] [blame] | 792 | } |
| 793 | } |
Jeremy Hylton | 2b724da | 2001-01-29 22:51:52 +0000 | [diff] [blame] | 794 | |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 795 | void |
Fred Drake | 1b190b4 | 2000-07-09 05:40:56 +0000 | [diff] [blame] | 796 | PyFrame_FastToLocals(PyFrameObject *f) |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 797 | { |
Guido van Rossum | f3e85a0 | 1997-01-20 04:20:52 +0000 | [diff] [blame] | 798 | /* Merge fast locals into f->f_locals */ |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 799 | PyObject *locals, *map; |
| 800 | PyObject **fast; |
| 801 | PyObject *error_type, *error_value, *error_traceback; |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 802 | PyCodeObject *co; |
Martin v. Löwis | 18e1655 | 2006-02-15 17:27:45 +0000 | [diff] [blame] | 803 | Py_ssize_t j; |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 804 | int ncells, nfreevars; |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 805 | if (f == NULL) |
| 806 | return; |
Guido van Rossum | 2271bf7 | 1995-07-18 14:30:34 +0000 | [diff] [blame] | 807 | locals = f->f_locals; |
| 808 | if (locals == NULL) { |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 809 | locals = f->f_locals = PyDict_New(); |
Guido van Rossum | 2271bf7 | 1995-07-18 14:30:34 +0000 | [diff] [blame] | 810 | if (locals == NULL) { |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 811 | PyErr_Clear(); /* Can't report it :-( */ |
Guido van Rossum | 2271bf7 | 1995-07-18 14:30:34 +0000 | [diff] [blame] | 812 | return; |
| 813 | } |
| 814 | } |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 815 | co = f->f_code; |
| 816 | map = co->co_varnames; |
Raymond Hettinger | 214b1c3 | 2004-07-02 06:41:07 +0000 | [diff] [blame] | 817 | if (!PyTuple_Check(map)) |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 818 | return; |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 819 | PyErr_Fetch(&error_type, &error_value, &error_traceback); |
Guido van Rossum | f3e85a0 | 1997-01-20 04:20:52 +0000 | [diff] [blame] | 820 | fast = f->f_localsplus; |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 821 | j = PyTuple_GET_SIZE(map); |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 822 | if (j > co->co_nlocals) |
| 823 | j = co->co_nlocals; |
| 824 | if (co->co_nlocals) |
Jeremy Hylton | 174d276 | 2003-10-21 18:10:28 +0000 | [diff] [blame] | 825 | map_to_dict(map, j, locals, fast, 0); |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 826 | ncells = PyTuple_GET_SIZE(co->co_cellvars); |
| 827 | nfreevars = PyTuple_GET_SIZE(co->co_freevars); |
| 828 | if (ncells || nfreevars) { |
| 829 | map_to_dict(co->co_cellvars, ncells, |
| 830 | locals, fast + co->co_nlocals, 1); |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 831 | /* If the namespace is unoptimized, then one of the |
| 832 | following cases applies: |
| 833 | 1. It does not contain free variables, because it |
| 834 | uses import * or is a top-level namespace. |
| 835 | 2. It is a class namespace. |
| 836 | We don't want to accidentally copy free variables |
| 837 | into the locals dict used by the class. |
| 838 | */ |
| 839 | if (co->co_flags & CO_OPTIMIZED) { |
| 840 | map_to_dict(co->co_freevars, nfreevars, |
| 841 | locals, fast + co->co_nlocals + ncells, 1); |
| 842 | } |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 843 | } |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 844 | PyErr_Restore(error_type, error_value, error_traceback); |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 845 | } |
| 846 | |
| 847 | void |
Fred Drake | 1b190b4 | 2000-07-09 05:40:56 +0000 | [diff] [blame] | 848 | PyFrame_LocalsToFast(PyFrameObject *f, int clear) |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 849 | { |
Guido van Rossum | f3e85a0 | 1997-01-20 04:20:52 +0000 | [diff] [blame] | 850 | /* Merge f->f_locals into fast locals */ |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 851 | PyObject *locals, *map; |
| 852 | PyObject **fast; |
| 853 | PyObject *error_type, *error_value, *error_traceback; |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 854 | PyCodeObject *co; |
Martin v. Löwis | 18e1655 | 2006-02-15 17:27:45 +0000 | [diff] [blame] | 855 | Py_ssize_t j; |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 856 | int ncells, nfreevars; |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 857 | if (f == NULL) |
| 858 | return; |
| 859 | locals = f->f_locals; |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 860 | co = f->f_code; |
| 861 | map = co->co_varnames; |
Jeremy Hylton | 24ea8d3 | 2002-04-20 04:46:55 +0000 | [diff] [blame] | 862 | if (locals == NULL) |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 863 | return; |
Raymond Hettinger | 214b1c3 | 2004-07-02 06:41:07 +0000 | [diff] [blame] | 864 | if (!PyTuple_Check(map)) |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 865 | return; |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 866 | PyErr_Fetch(&error_type, &error_value, &error_traceback); |
Guido van Rossum | f3e85a0 | 1997-01-20 04:20:52 +0000 | [diff] [blame] | 867 | fast = f->f_localsplus; |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 868 | j = PyTuple_GET_SIZE(map); |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 869 | if (j > co->co_nlocals) |
| 870 | j = co->co_nlocals; |
| 871 | if (co->co_nlocals) |
| 872 | dict_to_map(co->co_varnames, j, locals, fast, 0, clear); |
| 873 | ncells = PyTuple_GET_SIZE(co->co_cellvars); |
| 874 | nfreevars = PyTuple_GET_SIZE(co->co_freevars); |
| 875 | if (ncells || nfreevars) { |
| 876 | dict_to_map(co->co_cellvars, ncells, |
| 877 | locals, fast + co->co_nlocals, 1, clear); |
| 878 | dict_to_map(co->co_freevars, nfreevars, |
| 879 | locals, fast + co->co_nlocals + ncells, 1, |
Guido van Rossum | d8faa36 | 2007-04-27 19:54:29 +0000 | [diff] [blame] | 880 | clear); |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 881 | } |
Guido van Rossum | 1875247 | 1997-04-29 14:49:28 +0000 | [diff] [blame] | 882 | PyErr_Restore(error_type, error_value, error_traceback); |
Guido van Rossum | 1d5735e | 1994-08-30 08:27:36 +0000 | [diff] [blame] | 883 | } |
Guido van Rossum | 404b95d | 1997-08-05 02:09:46 +0000 | [diff] [blame] | 884 | |
| 885 | /* Clear out the free list */ |
| 886 | |
| 887 | void |
Fred Drake | 1b190b4 | 2000-07-09 05:40:56 +0000 | [diff] [blame] | 888 | PyFrame_Fini(void) |
Guido van Rossum | 404b95d | 1997-08-05 02:09:46 +0000 | [diff] [blame] | 889 | { |
| 890 | while (free_list != NULL) { |
| 891 | PyFrameObject *f = free_list; |
| 892 | free_list = free_list->f_back; |
Neil Schemenauer | 4f4817f | 2001-08-29 23:52:17 +0000 | [diff] [blame] | 893 | PyObject_GC_Del(f); |
Tim Peters | b7ba743 | 2002-04-13 05:21:47 +0000 | [diff] [blame] | 894 | --numfree; |
Guido van Rossum | 404b95d | 1997-08-05 02:09:46 +0000 | [diff] [blame] | 895 | } |
Tim Peters | b7ba743 | 2002-04-13 05:21:47 +0000 | [diff] [blame] | 896 | assert(numfree == 0); |
Neal Norwitz | c91ed40 | 2002-12-30 22:29:22 +0000 | [diff] [blame] | 897 | Py_XDECREF(builtin_object); |
| 898 | builtin_object = NULL; |
Guido van Rossum | 404b95d | 1997-08-05 02:09:46 +0000 | [diff] [blame] | 899 | } |