diff options
Diffstat (limited to 'src/cmd/eqn/lex.c')
| -rw-r--r-- | src/cmd/eqn/lex.c | 265 |
1 files changed, 265 insertions, 0 deletions
diff --git a/src/cmd/eqn/lex.c b/src/cmd/eqn/lex.c new file mode 100644 index 00000000..e535b869 --- /dev/null +++ b/src/cmd/eqn/lex.c @@ -0,0 +1,265 @@ +#include "e.h" +#include "y.tab.h" +#include <ctype.h> + +#define SSIZE 1000 +char token[SSIZE]; +int sp; + +void space(void); +void dodef(tbl *); +void define(int); +void ifdef(void); +void include(void); +void delim(void); + +yylex(void) +{ + register int c; + tbl *tp; + + begin: + while ((c = input()) == ' ' || c == '\n' || c == '\t') + ; + yylval = c; + switch (c) { + case EOF: + ERROR "unexpected end of input inside equation" WARNING; + return(EOF); + case '~': + return(SPACE); + case '^': + return(THIN); + /* case '\t': + return(TAB); + */ + case '{': + return('{'); + case '}': + return('}'); + case '"': + for (sp = 0; (c=input())!='"' && c != '\n'; ) { + if (c == '\\') + if ((c = input()) != '"') + token[sp++] = '\\'; + token[sp++] = c; + if (sp >= SSIZE) + ERROR "quoted string %.20s... too long", token FATAL; + } + token[sp] = '\0'; + yylval = (int) &token[0]; + if (c == '\n') + ERROR "missing \" in %.20s", token WARNING; + return(QTEXT); + } + if (!display && c == righteq) + return(EOF); + + unput(c); + getstr(token, SSIZE); + dprintf(".\tlex token = |%s|\n", token); + if ((tp = lookup(deftbl, token)) != NULL) { /* defined term */ + c = input(); + unput(c); + if (c == '(') /* macro with args */ + dodef(tp); + else { /* no args */ + unput(' '); + pbstr(tp->cval); + dprintf(".\tfound %s|=%s|\n", token, tp->cval); + } + goto begin; + } + + if ((tp = lookup(keytbl, token)) == NULL) /* not a keyword */ + return CONTIG; + + switch (tp->ival) { /* some kind of keyword */ + case DEFINE: case TDEFINE: case NDEFINE: + define(tp->ival); + break; + case IFDEF: + ifdef(); + break; + case DELIM: + delim(); + break; + case GSIZE: + globsize(); + break; + case GFONT: + globfont(); + break; + case INCLUDE: + include(); + break; + case SPACE: + space(); + break; + case DOTEQ: + /* .EQ inside equation -- should warn if at bottom level */ + break; + case DOTEN: + if (curfile == infile) + return EOF; + /* else ignore nested .EN */ + break; + default: + return tp->ival; + } + goto begin; +} + +void getstr(char *s, int n) +{ + register int c; + register char *p; + + p = s; + while ((c = input()) == ' ' || c == '\n') + ; + if (c == EOF) { + *s = 0; + return; + } + while (c != ' ' && c != '\t' && c != '\n' && c != '{' && c != '}' + && c != '"' && c != '~' && c != '^') { + if (!display && c == righteq) + break; + if (c == '(' && p > s) { /* might be defined(...) */ + *p = '\0'; + if (lookup(deftbl, s) != NULL) + break; + } + if (c == '\\') + if ((c = input()) != '"') + *p++ = '\\'; + *p++ = c; + if (--n <= 0) + ERROR "token %.20s... too long", s FATAL; + c = input(); + } + unput(c); + *p = '\0'; + yylval = (int) s; +} + +cstr(char *s, int quote, int maxs) +{ + int del, c, i; + + s[0] = 0; + while ((del=input()) == ' ' || del == '\t') + ; + if (quote) + for (i=0; (c=input()) != del && c != EOF;) { + s[i++] = c; + if (i >= maxs) + return(1); /* disaster */ + } + else { + if (del == '\n') + return(1); + s[0] = del; + for (i=1; (c=input())!=' ' && c!= '\t' && c!='\n' && c!=EOF;) { + s[i++] = c; + if (i >= maxs) + return(1); /* disaster */ + } + } + s[i] = '\0'; + if (c == EOF) + ERROR "Unexpected end of input at %.20s", s FATAL; + return(0); +} + +void define(int type) +{ + char *p1, *p2; + extern int ftune(char *, char *); + + getstr(token, SSIZE); /* get name */ + if (type != DEFINE) { + cstr(token, 1, SSIZE); /* skip the definition too */ + return; + } + p1 = strsave(token); + if (cstr(token, 1, SSIZE)) + ERROR "Unterminated definition at %.20s", token FATAL; + if (lookup(ftunetbl, p1) != NULL) { /* double tuning param */ + dprintf(".\ttune %s %s\n", p1, token); + ftune(p1, token); + } else { + p2 = strsave(token); + install(deftbl, p1, p2, 0); + dprintf(".\tname %s defined as %s\n", p1, p2); + } +} + +void ifdef(void) /* do body if name is defined */ +{ + char name[100], *p; + + getstr(name, sizeof(name)); /* get name */ + cstr(token, 1, SSIZE); /* and body */ + if (lookup(deftbl, name) != NULL) { /* found it */ + p = strsave(token); + pushsrc(Free, p); + pushsrc(String, p); + } +} + +char *spaceval = NULL; + +void space(void) /* collect line of form "space amt" to replace \x in output */ +{ + getstr(token, SSIZE); + spaceval = strsave(token); + dprintf(".\tsetting spaceval to %s\n", token); +} + +char *strsave(char *s) +{ + register char *q; + + q = malloc(strlen(s)+1); + if (q == NULL) + ERROR "out of space in strsave on %s", s FATAL; + strcpy(q, s); + return(q); +} + +void include(void) +{ + char name[100]; + FILE *fin; + int c; + extern int errno; + + while ((c = input()) == ' ') + ; + unput(c); + cstr(name, c == '"', sizeof(name)); /* gets it quoted or not */ + if ((fin = fopen(name, "r")) == NULL) + ERROR "can't open file %s", name FATAL; + errno = 0; + curfile++; + curfile->fin = fin; + curfile->fname = strsave(name); + curfile->lineno = 0; + printf(".lf 1 %s\n", curfile->fname); + pushsrc(File, curfile->fname); +} + +void delim(void) +{ + yyval = eqnreg = 0; + if (cstr(token, 0, SSIZE)) + ERROR "Bizarre delimiters" FATAL; + lefteq = token[0]; + righteq = token[1]; + if (!isprint(lefteq) || !isprint(righteq)) + ERROR "Bizarre delimiters" FATAL; + if (lefteq == 'o' && righteq == 'f') + lefteq = righteq = '\0'; +} |