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diff --git a/Build/source/texk/web2c/luatexdir/tex/primitive.w b/Build/source/texk/web2c/luatexdir/tex/primitive.w new file mode 100644 index 00000000000..89db63fbeaa --- /dev/null +++ b/Build/source/texk/web2c/luatexdir/tex/primitive.w @@ -0,0 +1,664 @@ +% primitive.w + +% Copyright 2008-2010 Taco Hoekwater <taco@@luatex.org> + +% This file is part of LuaTeX. + +% LuaTeX is free software; you can redistribute it and/or modify it under +% the terms of the GNU General Public License as published by the Free +% Software Foundation; either version 2 of the License, or (at your +% option) any later version. + +% LuaTeX is distributed in the hope that it will be useful, but WITHOUT +% ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or +% FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public +% License for more details. + +% You should have received a copy of the GNU General Public License along +% with LuaTeX; if not, see <http://www.gnu.org/licenses/>. + +@ @c +#include "ptexlib.h" + + +static const char _svn_version[] = + "$Id: primitive.w 3587 2010-04-03 14:32:25Z taco $ " + "$URL: http://foundry.supelec.fr/svn/luatex/tags/beta-0.60.0/source/texk/web2c/luatexdir/tex/primitive.w $"; + + +@ Control sequences are stored and retrieved by means of a fairly standard hash +table algorithm called the method of ``coalescing lists'' (cf.\ Algorithm 6.4C +in {\sl The Art of Computer Programming\/}). Once a control sequence enters the +table, it is never removed, because there are complicated situations +involving \.{\\gdef} where the removal of a control sequence at the end of +a group would be a mistake preventable only by the introduction of a +complicated reference-count mechanism. + +The actual sequence of letters forming a control sequence identifier is +stored in the |str_pool| array together with all the other strings. An +auxiliary array |hash| consists of items with two halfword fields per +word. The first of these, called |next(p)|, points to the next identifier +belonging to the same coalesced list as the identifier corresponding to~|p|; +and the other, called |text(p)|, points to the |str_start| entry for +|p|'s identifier. If position~|p| of the hash table is empty, we have +|text(p)=0|; if position |p| is either empty or the end of a coalesced +hash list, we have |next(p)=0|. An auxiliary pointer variable called +|hash_used| is maintained in such a way that all locations |p>=hash_used| +are nonempty. The global variable |cs_count| tells how many multiletter +control sequences have been defined, if statistics are being kept. + +A global boolean variable called |no_new_control_sequence| is set to +|true| during the time that new hash table entries are forbidden. + +@c +two_halves *hash; /* the hash table */ +halfword hash_used; /* allocation pointer for |hash| */ +int hash_extra; /* |hash_extra=hash| above |eqtb_size| */ +halfword hash_top; /* maximum of the hash array */ +halfword hash_high; /* pointer to next high hash location */ +boolean no_new_control_sequence; /* are new identifiers legal? */ +int cs_count; /* total number of known identifiers */ + +#define hash_is_full (hash_used==hash_base) /* test if all positions are occupied */ + +@ \.{\\primitive} support needs a few extra variables and definitions + +@c +#define prim_base 1 + +@ The arrays |prim| and |prim_eqtb| are used for name -> cmd,chr lookups. + + The are modelled after |hash| and |eqtb|, except that primitives do not + have an |eq_level|, that field is replaced by |origin|. + +@c +#define prim_next(a) prim[(a)].lhfield /* link for coalesced lists */ +#define prim_text(a) prim[(a)].rh /* string number for control sequence name */ +#define prim_is_full (prim_used==prim_base) /* test if all positions are occupied */ + +#define prim_origin_field(a) (a).hh.b1 +#define prim_eq_type_field(a) (a).hh.b0 +#define prim_equiv_field(a) (a).hh.rh +#define prim_origin(a) prim_origin_field(prim_eqtb[(a)]) /* level of definition */ +#define prim_eq_type(a) prim_eq_type_field(prim_eqtb[(a)]) /* command code for equivalent */ +#define prim_equiv(a) prim_equiv_field(prim_eqtb[(a)]) /* equivalent value */ + +static pointer prim_used; /* allocation pointer for |prim| */ +static two_halves prim[(prim_size + 1)]; /* the primitives table */ +static memory_word prim_eqtb[(prim_size + 1)]; + +@ The array |prim_data| works the other way around, it is used for + cmd,chr -> name lookups. + +@c +typedef struct prim_info { + halfword subids; /* number of name entries */ + halfword offset; /* offset to be used for |chr_code|s */ + str_number *names; /* array of names */ +} prim_info; + +static prim_info prim_data[(last_cmd + 1)]; + +@ initialize the memory arrays +@c +void init_primitives(void) +{ + int k; + memset(prim_data, 0, (sizeof(prim_info) * (last_cmd + 1))); + memset(prim, 0, (sizeof(two_halves) * (prim_size + 1))); + memset(prim_eqtb, 0, (sizeof(memory_word) * (prim_size + 1))); + for (k = 0; k <= prim_size; k++) + prim_eq_type(k) = undefined_cs_cmd; +} + +void ini_init_primitives(void) +{ + prim_used = prim_size; /* nothing is used */ +} + + +@ The value of |hash_prime| should be roughly 85\%! of |hash_size|, and it + should be a prime number. The theory of hashing tells us to expect fewer + than two table probes, on the average, when the search is successful. + [See J.~S. Vitter, {\sl Journal of the ACM\/ \bf30} (1983), 231--258.] + @^Vitter, Jeffrey Scott@> + +@c +static halfword compute_hash(const char *j, unsigned int l, + halfword prime_number) +{ + unsigned int k; + halfword h = (unsigned char) *j; + for (k = 1; k <= l - 1; k++) { + h = h + h + (unsigned char) *(j + k); + while (h >= prime_number) + h = h - prime_number; + } + return h; +} + + +@ Here is the subroutine that searches the primitive table for an identifier +@c +pointer prim_lookup(str_number s) +{ + int h; /* hash code */ + pointer p; /* index in |hash| array */ + unsigned char *j; + unsigned l; + if (s < STRING_OFFSET) { + p = s; + if ((p < 0) || (get_prim_eq_type(p) == undefined_cs_cmd)) { + p = undefined_primitive; + } + } else { + j = str_string(s); + l = (unsigned) str_length(s); + h = compute_hash((char *) j, l, prim_prime); + p = h + prim_base; /* we start searching here; note that |0<=h<hash_prime| */ + while (1) { + if (prim_text(p) > 0) + if (str_length(prim_text(p)) == l) + if (str_eq_str(prim_text(p), s)) + goto FOUND; + if (prim_next(p) == 0) { + if (no_new_control_sequence) { + p = undefined_primitive; + } else { + /* Insert a new primitive after |p|, then make |p| point to it */ + if (prim_text(p) > 0) { + do { /* search for an empty location in |prim| */ + if (prim_is_full) + overflow("primitive size", prim_size); + decr(prim_used); + } while (prim_text(prim_used) != 0); + prim_next(p) = prim_used; + p = prim_used; + } + prim_text(p) = s; + } + goto FOUND; + } + p = prim_next(p); + } + } + FOUND: + return p; +} + +@ how to test a csname for primitive-ness +@c +boolean is_primitive(str_number csname) +{ + int n, m; + char *ss; + m = prim_lookup(csname); + ss = makecstring(csname); + n = string_lookup(ss, str_length(csname)); + free(ss); + return ((n != undefined_cs_cmd) && + (m != undefined_primitive) && + (eq_type(n) == prim_eq_type(m)) && (equiv(n) == prim_equiv(m))); +} + + +@ a few simple accessors +@c +quarterword get_prim_eq_type(int p) +{ + return prim_eq_type(p); +} + +quarterword get_prim_origin(int p) +{ + return prim_origin(p); +} + +halfword get_prim_equiv(int p) +{ + return prim_equiv(p); +} + +str_number get_prim_text(int p) +{ + return prim_text(p); +} + + +@ dumping and undumping +@c +void dump_primitives(void) +{ + int p, q; + for (p = 0; p <= prim_size; p++) + dump_hh(prim[p]); + for (p = 0; p <= prim_size; p++) + dump_wd(prim_eqtb[p]); + for (p = 0; p <= last_cmd; p++) { + dump_int(prim_data[p].offset); + dump_int(prim_data[p].subids); + for (q = 0; q < prim_data[p].subids; q++) { + dump_int(prim_data[p].names[q]); + } + } +} + +void undump_primitives(void) +{ + int p, q; + for (p = 0; p <= prim_size; p++) + undump_hh(prim[p]); + for (p = 0; p <= prim_size; p++) + undump_wd(prim_eqtb[p]); + + for (p = 0; p <= last_cmd; p++) { + undump_int(prim_data[p].offset); + undump_int(prim_data[p].subids); + if (prim_data[p].subids > 0) { + prim_data[p].names = (str_number *) + xmalloc((unsigned) + ((unsigned) prim_data[p].subids * + sizeof(str_number *))); + for (q = 0; q < prim_data[p].subids; q++) + undump_int(prim_data[p].names[q]); + } + } +} + +@ We need to put \TeX's ``primitive'' control sequences into the hash + table, together with their command code (which will be the |eq_type|) + and an operand (which will be the |equiv|). The |primitive| procedure + does this, in a way that no \TeX\ user can. The global value |cur_val| + contains the new |eqtb| pointer after |primitive| has acted. + + +@ Because the definitions of the actual user-accessible name of a + primitive can be postponed until runtime, the function |primitive_def| + is needed that does nothing except creating the control sequence name. + +@c +void primitive_def(const char *s, size_t l, quarterword c, halfword o) +{ + int nncs = no_new_control_sequence; + no_new_control_sequence = false; + cur_val = string_lookup(s, l); /* this creates the |text()| string */ + no_new_control_sequence = nncs; + eq_level(cur_val) = level_one; + eq_type(cur_val) = c; + equiv(cur_val) = o; +} + +@ The function |store_primitive_name| sets up the bookkeeping for the + reverse lookup. It is quite paranoid, because it is easy to mess this up + accidentally. + + The |offset| is needed because sometimes character codes (in |o|) + are indices into |eqtb| or are offset by a magical value to make + sure they do not conflict with something else. We don't want the + |prim_data[c].names| to have too many entries as it will just be + wasted room, so |offset| is substracted from |o| because creating + or accessing the array. The |assert(idx<=0xFFFF)| is not strictly + needed, but it helps catch errors of this kind. + +@c +void +store_primitive_name(str_number s, quarterword c, halfword o, halfword offset) +{ + int idx; + if (prim_data[c].offset != 0 && prim_data[c].offset != offset) { + assert(false); + } + prim_data[c].offset = offset; + idx = ((int) o - offset); + assert(idx >= 0); + assert(idx <= 0xFFFF); + if (prim_data[c].subids < (idx + 1)) { + str_number *new = + (str_number *) xcalloc((unsigned) (idx + 1), sizeof(str_number *)); + if (prim_data[c].names != NULL) { + assert(prim_data[c].subids); + memcpy(new, (prim_data[c].names), + (unsigned) (prim_data[c].subids) * sizeof(str_number)); + free(prim_data[c].names); + } + prim_data[c].names = new; + prim_data[c].subids = idx + 1; + } + prim_data[c].names[idx] = s; +} + +@ Compared to tex82, |primitive| has two extra parameters. The |off| is an offset + that will be passed on to |store_primitive_name|, the |cmd_origin| is the bit + that is used to group primitives by originator. + +@c +void +primitive(const char *thes, quarterword c, halfword o, halfword off, + int cmd_origin) +{ + int prim_val; /* needed to fill |prim_eqtb| */ + str_number ss; + assert(o >= off); + ss = maketexstring(thes); + if (cmd_origin == tex_command || cmd_origin == core_command) { + primitive_def(thes, strlen(thes), c, o); + } + prim_val = prim_lookup(ss); + prim_origin(prim_val) = (quarterword) cmd_origin; + prim_eq_type(prim_val) = c; + prim_equiv(prim_val) = o; + store_primitive_name(ss, c, o, off); +} + + + +@ Here is a helper that does the actual hash insertion. + +@c +static halfword insert_id(halfword p, const unsigned char *j, unsigned int l) +{ + unsigned saved_cur_length; + unsigned saved_cur_string_size; + unsigned char *saved_cur_string; + const unsigned char *k; + /* This code far from ideal: the existance of |hash_extra| changes + all the potential (short) coalesced lists into a single (long) + one. This will create a slowdown. */ + if (cs_text(p) > 0) { + if (hash_high < hash_extra) { + incr(hash_high); + /* can't use |eqtb_top| here (perhaps because that is not finalized + yet when called from |primitive|?) */ + cs_next(p) = hash_high + eqtb_size; + p = cs_next(p); + } else { + do { + if (hash_is_full) + overflow("hash size", (unsigned) (hash_size + hash_extra)); + decr(hash_used); + } while (cs_text(hash_used) != 0); /* search for an empty location in |hash| */ + cs_next(p) = hash_used; + p = hash_used; + } + } + saved_cur_length = cur_length; + saved_cur_string = cur_string; + saved_cur_string_size = cur_string_size; + reset_cur_string(); + for (k = j; k <= j + l - 1; k++) + append_char(*k); + cs_text(p) = make_string(); + cur_length = saved_cur_length; + cur_string = saved_cur_string; + cur_string_size = saved_cur_string_size; + incr(cs_count); + return p; +} + + +@ Here is the subroutine that searches the hash table for an identifier + that matches a given string of length |l>1| appearing in |buffer[j.. + (j+l-1)]|. If the identifier is found, the corresponding hash table address + is returned. Otherwise, if the global variable |no_new_control_sequence| + is |true|, the dummy address |undefined_control_sequence| is returned. + Otherwise the identifier is inserted into the hash table and its location + is returned. + +@c +pointer id_lookup(int j, int l) +{ /* search the hash table */ + int h; /* hash code */ + pointer p; /* index in |hash| array */ + + h = compute_hash((char *) (buffer + j), (unsigned) l, hash_prime); +#ifdef VERBOSE + { + unsigned char *todo = xmalloc(l + 2); + strncpy(todo, (buffer + j), l); + todo[l] = '\0'; + todo[l + 1] = '\0'; + fprintf(stdout, "id_lookup(%s)\n", todo); + free(todo); + } +#endif + p = h + hash_base; /* we start searching here; note that |0<=h<hash_prime| */ + while (1) { + if (cs_text(p) > 0) + if (str_length(cs_text(p)) == (unsigned) l) + if (str_eq_buf(cs_text(p), j)) + goto FOUND; + if (cs_next(p) == 0) { + if (no_new_control_sequence) { + p = undefined_control_sequence; + } else { + p = insert_id(p, (buffer + j), (unsigned) l); + } + goto FOUND; + } + p = cs_next(p); + } + FOUND: + return p; +} + +@ Here is a similar subroutine for finding a primitive in the hash. +This one is based on a C string. + +@c +pointer string_lookup(const char *s, size_t l) +{ /* search the hash table */ + int h; /* hash code */ + pointer p; /* index in |hash| array */ + h = compute_hash(s, (unsigned) l, hash_prime); + p = h + hash_base; /* we start searching here; note that |0<=h<hash_prime| */ + while (1) { + if (cs_text(p) > 0) + if (str_eq_cstr(cs_text(p), s, l)) + goto FOUND; + if (cs_next(p) == 0) { + if (no_new_control_sequence) { + p = undefined_control_sequence; + } else { + p = insert_id(p, (const unsigned char *) s, (unsigned) l); + } + goto FOUND; + } + p = cs_next(p); + } + FOUND: + return p; +} + +@ The |print_cmd_chr| routine prints a symbolic interpretation of a + command code and its modifier. This is used in certain `\.{You can\'t}' + error messages, and in the implementation of diagnostic routines like + \.{\\show}. + + The body of |print_cmd_chr| use to be a rather tedious listing of print + commands, and most of it was essentially an inverse to the |primitive| + routine that enters a \TeX\ primitive into |eqtb|. + + Thanks to |prim_data|, there is no need for all that tediousness. What + is left of |primt_cnd_chr| are just the exceptions to the general rule + that the |cmd,chr_code| pair represents in a single primitive command. + +@c +#define chr_cmd(A) do { tprint(A); print(chr_code); } while (0) + +void prim_cmd_chr(quarterword cmd, halfword chr_code) +{ + int idx = chr_code - prim_data[cmd].offset; + if (cmd <= last_cmd && + idx >= 0 && idx < prim_data[cmd].subids && + prim_data[cmd].names != NULL && prim_data[cmd].names[idx] != 0) { + tprint("\\"); + print(prim_data[cmd].names[idx]); + } else { + /* TEX82 didn't print the |cmd,idx| information, but it may be useful */ + tprint("[unknown command code! ("); + print_int(cmd); + tprint(", "); + print_int(idx); + tprint(")]"); + } +} + +void print_cmd_chr(quarterword cmd, halfword chr_code) +{ + int n; /* temp variable */ + switch (cmd) { + case left_brace_cmd: + chr_cmd("begin-group character "); + break; + case right_brace_cmd: + chr_cmd("end-group character "); + break; + case math_shift_cmd: + chr_cmd("math shift character "); + break; + case mac_param_cmd: + if (chr_code == tab_mark_cmd_code) + tprint_esc("alignmark"); + else + chr_cmd("macro parameter character "); + break; + case sup_mark_cmd: + chr_cmd("superscript character "); + break; + case sub_mark_cmd: + chr_cmd("subscript character "); + break; + case endv_cmd: + tprint("end of alignment template"); + break; + case spacer_cmd: + chr_cmd("blank space "); + break; + case letter_cmd: + chr_cmd("the letter "); + break; + case other_char_cmd: + chr_cmd("the character "); + break; + case tab_mark_cmd: + if (chr_code == span_code) + tprint_esc("span"); + else if (chr_code == tab_mark_cmd_code) + tprint_esc("aligntab"); + else + chr_cmd("alignment tab character "); + break; + case if_test_cmd: + if (chr_code >= unless_code) + tprint_esc("unless"); + prim_cmd_chr(cmd, (chr_code % unless_code)); + break; + case char_given_cmd: + tprint_esc("char"); + print_hex(chr_code); + break; + case math_given_cmd: + tprint_esc("mathchar"); + show_mathcode_value(mathchar_from_integer(chr_code, tex_mathcode)); + break; + case omath_given_cmd: + tprint_esc("omathchar"); + show_mathcode_value(mathchar_from_integer(chr_code, aleph_mathcode)); + break; + case xmath_given_cmd: + tprint_esc("Umathchar"); + show_mathcode_value(mathchar_from_integer(chr_code, xetex_mathcode)); + break; + case set_font_cmd: + tprint("select font "); + tprint(font_name(chr_code)); + if (font_size(chr_code) != font_dsize(chr_code)) { + tprint(" at "); + print_scaled(font_size(chr_code)); + tprint("pt"); + } + break; + case undefined_cs_cmd: + tprint("undefined"); + break; + case call_cmd: + case long_call_cmd: + case outer_call_cmd: + case long_outer_call_cmd: + n = cmd - call_cmd; + if (token_info(token_link(chr_code)) == protected_token) + n = n + 4; + if (odd(n / 4)) + tprint_esc("protected"); + if (odd(n)) + tprint_esc("long"); + if (odd(n / 2)) + tprint_esc("outer"); + if (n > 0) + tprint(" "); + tprint("macro"); + break; + case extension_cmd: + if (chr_code < prim_data[cmd].subids && + prim_data[cmd].names[chr_code] != 0) { + prim_cmd_chr(cmd, chr_code); + } else { + tprint("[unknown extension! ("); + print_int(chr_code); + tprint(")]"); + + } + break; + case set_ocp_cmd: + tprint("select ocp "); + slow_print(ocp_name(chr_code)); + break; + case set_ocp_list_cmd: + tprint("select ocp list "); + break; + case assign_glue_cmd: + case assign_mu_glue_cmd: + if (chr_code < skip_base) { + prim_cmd_chr(cmd, chr_code); + } else if (chr_code < mu_skip_base) { + tprint_esc("skip"); + print_int(chr_code - skip_base); + } else { + tprint_esc("muskip"); + print_int(chr_code - mu_skip_base); + } + break; + case assign_toks_cmd: + if (chr_code >= toks_base) { + tprint_esc("toks"); + print_int(chr_code - toks_base); + } else { + prim_cmd_chr(cmd, chr_code); + } + break; + case assign_int_cmd: + if (chr_code < count_base) { + prim_cmd_chr(cmd, chr_code); + } else { + tprint_esc("count"); + print_int(chr_code - count_base); + } + break; + case assign_attr_cmd: + tprint_esc("attribute"); + print_int(chr_code - attribute_base); + break; + case assign_dimen_cmd: + if (chr_code < scaled_base) { + prim_cmd_chr(cmd, chr_code); + } else { + tprint_esc("dimen"); + print_int(chr_code - scaled_base); + } + break; + default: + /* these are most commands, actually */ + prim_cmd_chr(cmd, chr_code); + break; + } +} |