/* String object implementation */ #include #include "PROTO.h" #include "object.h" #include "stringobject.h" #include "intobject.h" #include "objimpl.h" object * newsizedstringobject(str, size) char *str; int size; { register stringobject *op = (stringobject *) malloc(sizeof(stringobject) + size * sizeof(char)); if (op == NULL) { errno = ENOMEM; } else { NEWREF(op); op->ob_type = &Stringtype; op->ob_size = size; if (str != NULL) memcpy(op->ob_sval, str, size); op->ob_sval[size] = '\0'; } return (object *) op; } object * newstringobject(str) char *str; { register unsigned int size = strlen(str); register stringobject *op = (stringobject *) malloc(sizeof(stringobject) + size * sizeof(char)); if (op == NULL) { errno = ENOMEM; } else { NEWREF(op); op->ob_type = &Stringtype; op->ob_size = size; strcpy(op->ob_sval, str); } return (object *) op; } unsigned int getstringsize(op) register object *op; { if (!is_stringobject(op)) { errno = EBADF; return -1; } return ((stringobject *)op) -> ob_size; } /*const*/ char * getstringvalue(op) register object *op; { if (!is_stringobject(op)) { errno = EBADF; return NULL; } return ((stringobject *)op) -> ob_sval; } /* Methods */ static void stringprint(op, fp, flags) stringobject *op; FILE *fp; int flags; { int i; char c; if (flags & PRINT_RAW) { fwrite(op->ob_sval, 1, (int) op->ob_size, fp); return; } fprintf(fp, "'"); for (i = 0; i < op->ob_size; i++) { c = op->ob_sval[i]; if (c == '\'' || c == '\\') fprintf(fp, "\\%c", c); else if (c < ' ' || c >= 0177) fprintf(fp, "\\%03o", c&0377); else putc(c, fp); } fprintf(fp, "'"); } static object * stringrepr(op) register stringobject *op; { /* XXX overflow? */ int newsize = 2 + 4 * op->ob_size * sizeof(char); object *v = newsizedstringobject((char *)NULL, newsize); if (v == NULL) { errno = ENOMEM; } else { register int i; register char c; register char *p; NEWREF(v); v->ob_type = &Stringtype; ((stringobject *)v)->ob_size = newsize; p = ((stringobject *)v)->ob_sval; *p++ = '\''; for (i = 0; i < op->ob_size; i++) { c = op->ob_sval[i]; if (c == '\'' || c == '\\') *p++ = '\\', *p++ = c; else if (c < ' ' || c >= 0177) { sprintf(p, "\\%03o", c&0377); while (*p != '\0') p++; } else *p++ = c; } *p++ = '\''; *p = '\0'; resizestring(&v, (int) (p - ((stringobject *)v)->ob_sval)); } return v; } static int stringlength(a) stringobject *a; { return a->ob_size; } static object * stringconcat(a, bb) register stringobject *a; register object *bb; { register unsigned int size; register stringobject *op; if (!is_stringobject(bb)) { errno = EINVAL; return NULL; } #define b ((stringobject *)bb) /* Optimize cases with empty left or right operand */ if (a->ob_size == 0) { INCREF(bb); return bb; } if (b->ob_size == 0) { INCREF(a); return (object *)a; } size = a->ob_size + b->ob_size; op = (stringobject *) malloc(sizeof(stringobject) + size * sizeof(char)); if (op == NULL) { errno = ENOMEM; } else { NEWREF(op); op->ob_type = &Stringtype; op->ob_size = size; memcpy(op->ob_sval, a->ob_sval, (int) a->ob_size); memcpy(op->ob_sval + a->ob_size, b->ob_sval, (int) b->ob_size); op->ob_sval[size] = '\0'; } return (object *) op; #undef b } static object * stringrepeat(a, n) register stringobject *a; register int n; { register int i; register unsigned int size; register stringobject *op; if (n < 0) n = 0; size = a->ob_size * n; if (size == a->ob_size) { INCREF(a); return (object *)a; } op = (stringobject *) malloc(sizeof(stringobject) + size * sizeof(char)); if (op == NULL) { errno = ENOMEM; } else { NEWREF(op); op->ob_type = &Stringtype; op->ob_size = size; for (i = 0; i < size; i += a->ob_size) memcpy(op->ob_sval+i, a->ob_sval, (int) a->ob_size); op->ob_sval[size] = '\0'; } return (object *) op; } /* String slice a[i:j] consists of characters a[i] ... a[j-1] */ static object * stringslice(a, i, j) register stringobject *a; register int i, j; /* May be negative! */ { if (i < 0) i = 0; if (j < 0) j = 0; /* Avoid signed/unsigned bug in next line */ if (j > a->ob_size) j = a->ob_size; if (i == 0 && j == a->ob_size) { /* It's the same as a */ INCREF(a); return (object *)a; } if (j < i) j = i; return newsizedstringobject(a->ob_sval + i, (int) (j-i)); } static object * stringitem(a, i) stringobject *a; register int i; { if (i < 0 || i >= a->ob_size) { errno = EDOM; return NULL; } return stringslice(a, i, i+1); } static int stringcompare(a, b) stringobject *a, *b; { /* XXX should use memcmp on shortest size, then compare lengths */ return strcmp(a->ob_sval, b->ob_sval); } static sequence_methods string_as_sequence = { stringlength, /*tp_length*/ stringconcat, /*tp_concat*/ stringrepeat, /*tp_repeat*/ stringitem, /*tp_item*/ stringslice, /*tp_slice*/ 0, /*tp_ass_item*/ 0, /*tp_ass_slice*/ }; typeobject Stringtype = { OB_HEAD_INIT(&Typetype) 0, "string", sizeof(stringobject), sizeof(char), free, /*tp_dealloc*/ stringprint, /*tp_print*/ 0, /*tp_getattr*/ 0, /*tp_setattr*/ stringcompare, /*tp_compare*/ stringrepr, /*tp_repr*/ 0, /*tp_as_number*/ &string_as_sequence, /*tp_as_sequence*/ 0, /*tp_as_mapping*/ }; void joinstring(pv, w) register object **pv; register object *w; { register object *v; if (*pv == NULL || w == NULL || !is_stringobject(*pv)) return; v = stringconcat((stringobject *) *pv, w); DECREF(*pv); *pv = v; } /* The following function breaks the notion that strings are immutable: it changes the size of a string. We get away with this only if there is only one module referencing the object. You can also think of it as creating a new string object and destroying the old one, only more efficiently. In any case, don't use this if the string may already be known to some other part of the code... */ int resizestring(pv, newsize) object **pv; int newsize; { register stringobject *v; v = (stringobject *) *pv; if (!is_stringobject(v) || v->ob_refcnt != 1) { *pv = 0; DECREF(v); return errno = EBADF; } *pv = (object *) realloc((char *)v, sizeof(stringobject) + newsize * sizeof(char)); if (*pv == NULL) { DECREF(v); return errno = ENOMEM; } v = (stringobject *) *pv; v->ob_size = newsize; v->ob_sval[newsize] = '\0'; return 0; }