diff options
Diffstat (limited to 'scan.c')
| -rw-r--r-- | scan.c | 50 |
1 files changed, 35 insertions, 15 deletions
@@ -16,10 +16,14 @@ struct buffer { struct scanner { int chr; bool usebuf; + FILE *file; struct location loc; struct buffer buf; + struct scanner *next; }; +static struct scanner *scanner; + static void bufadd(struct buffer *b, char c) { @@ -51,16 +55,16 @@ nextchar(struct scanner *s) if (s->usebuf) bufadd(&s->buf, s->chr); for (;;) { - s->chr = getchar(); + s->chr = getc(s->file); if (s->chr == '\n') ++s->loc.line, s->loc.col = 1; else ++s->loc.col; if (s->chr != '\\') break; - c = getchar(); + c = getc(s->file); if (c != '\n') { - ungetc(c, stdin); + ungetc(c, s->file); break; } ++s->loc.line, s->loc.col = 1; @@ -337,7 +341,7 @@ again: loc = s->loc; nextchar(s); if (s->chr != '.') { - ungetc(s->chr, stdout); + ungetc(s->chr, s->file); s->loc = loc; s->chr = '.'; return TPERIOD; @@ -372,32 +376,48 @@ again: } } -struct scanner * -mkscanner(const char *file) +int +scanfrom(const char *name) { struct scanner *s; + FILE *file; + if (name) { + file = fopen(name, "r"); + if (!file) + return -1; + } else { + file = stdin; + name = "<stdin>"; + } s = xmalloc(sizeof(*s)); + s->file = file; s->buf.str = NULL; s->buf.len = 0; s->buf.cap = 0; s->usebuf = false; - s->loc.file = file; + s->loc.file = name; s->loc.line = 1; s->loc.col = 0; + s->next = scanner; + scanner = s; nextchar(s); - - return s; + return 0; } void -scan(struct scanner *s, struct token *t) +scan(struct token *t) { - t->loc = s->loc; - t->kind = scankind(s); - if (s->usebuf) { - t->lit = bufget(&s->buf); - s->usebuf = false; + for (;;) { + t->loc = scanner->loc; + t->kind = scankind(scanner); + if (t->kind != TEOF || !scanner->next) + break; + scanner = scanner->next; + } + if (scanner->usebuf) { + t->lit = bufget(&scanner->buf); + scanner->usebuf = false; } else { t->lit = NULL; } |