| Guido van Rossum | 85a5fbb | 1990-10-14 12:07:46 +0000 | [diff] [blame] | 1 | /* Grammar interface */ |
| 2 | |
| 3 | #include "bitset.h" /* Sigh... */ |
| 4 | |
| 5 | /* A label of an arc */ |
| 6 | |
| 7 | typedef struct _label { |
| 8 | int lb_type; |
| 9 | char *lb_str; |
| 10 | } label; |
| 11 | |
| 12 | #define EMPTY 0 /* Label number 0 is by definition the empty label */ |
| 13 | |
| 14 | /* A list of labels */ |
| 15 | |
| 16 | typedef struct _labellist { |
| 17 | int ll_nlabels; |
| 18 | label *ll_label; |
| 19 | } labellist; |
| 20 | |
| 21 | /* An arc from one state to another */ |
| 22 | |
| 23 | typedef struct _arc { |
| 24 | short a_lbl; /* Label of this arc */ |
| 25 | short a_arrow; /* State where this arc goes to */ |
| 26 | } arc; |
| 27 | |
| 28 | /* A state in a DFA */ |
| 29 | |
| 30 | typedef struct _state { |
| 31 | int s_narcs; |
| 32 | arc *s_arc; /* Array of arcs */ |
| 33 | |
| 34 | /* Optional accelerators */ |
| 35 | int s_lower; /* Lowest label index */ |
| 36 | int s_upper; /* Highest label index */ |
| 37 | int *s_accel; /* Accelerator */ |
| 38 | int s_accept; /* Nonzero for accepting state */ |
| 39 | } state; |
| 40 | |
| 41 | /* A DFA */ |
| 42 | |
| 43 | typedef struct _dfa { |
| 44 | int d_type; /* Non-terminal this represents */ |
| 45 | char *d_name; /* For printing */ |
| 46 | int d_initial; /* Initial state */ |
| 47 | int d_nstates; |
| 48 | state *d_state; /* Array of states */ |
| 49 | bitset d_first; |
| 50 | } dfa; |
| 51 | |
| 52 | /* A grammar */ |
| 53 | |
| 54 | typedef struct _grammar { |
| 55 | int g_ndfas; |
| 56 | dfa *g_dfa; /* Array of DFAs */ |
| 57 | labellist g_ll; |
| 58 | int g_start; /* Start symbol of the grammar */ |
| 59 | int g_accel; /* Set if accelerators present */ |
| 60 | } grammar; |
| 61 | |
| 62 | /* FUNCTIONS */ |
| 63 | |
| 64 | grammar *newgrammar PROTO((int start)); |
| 65 | dfa *adddfa PROTO((grammar *g, int type, char *name)); |
| 66 | int addstate PROTO((dfa *d)); |
| 67 | void addarc PROTO((dfa *d, int from, int to, int lbl)); |
| 68 | dfa *finddfa PROTO((grammar *g, int type)); |
| 69 | char *typename PROTO((grammar *g, int lbl)); |
| 70 | |
| 71 | int addlabel PROTO((labellist *ll, int type, char *str)); |
| 72 | int findlabel PROTO((labellist *ll, int type, char *str)); |
| 73 | char *labelrepr PROTO((label *lb)); |
| 74 | void translatelabels PROTO((grammar *g)); |
| 75 | |
| 76 | void addfirstsets PROTO((grammar *g)); |
| 77 | |
| 78 | void addaccellerators PROTO((grammar *g)); |