ref: 15ef27b9b747e452e17642b36bfd996cfb5fe9ff
dir: /cc1/cpp.c/
#include <ctype.h> #include <inttypes.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include "../inc/sizes.h" #include "../inc/cc.h" #include "cc1.h" /* TODO: preprocessor error must not rise recover */ static char * define(char *s) { char *t, name[IDENTSIZ+1]; size_t len; Symbol *sym; if (!isalnum(*s) && *s != '_') goto bad_define; for (t = s; isalnum(*t) || *t == '_'; ++t) /* nothing */; if ((len = t - s) > IDENTSIZ) goto too_long; strncpy(name, s, len); name[len] = '\0'; sym = install(name, NS_CPP); while (isspace(*t)) ++t; for (s = t + strlen(t); isspace(*--s); *s = '\0') /* nothing */; sym->u.s = xstrdup(t); return s+1; too_long: error("macro identifier too long"); bad_define: error("macro names must be identifiers"); } static char * include(char *s) { char fname[FILENAME_MAX], delim, c, *p; size_t len; if ((c = *s++) == '>') delim = '>'; else if (c == '"') delim = '"'; else goto bad_include; for (p = s; (c = *p) && c != delim; ++p) /* nothing */; if (c == '\0') goto bad_include; len = p - s; if (delim == '"') { if (len >= FILENAME_MAX) goto too_long; strncpy(fname, s, len); fname[len] = '\0'; if (!addinput(fname)) goto not_found; } else { abort(); } return p+1; not_found: error("included file '%s' not found", fname); too_long: error("file name in include too long"); bad_include: error("#include expects \"FILENAME\" or <FILENAME>"); } static char * line(char *s) { char *p, *q; if (!isdigit(*p)) goto bad_line; for (p = s; isdigit(*p); ++p) /* nothing */; switch (*p) { case ' ': case '\t': while (isspace(*p)) ++p; if (*p != '"') goto bad_line; for (q = p+1; *q && *q != '"'; ++q) /* nothing */; if (*q == '\0') goto bad_line; *q = '\0'; setfname(p); p = q+1; /* passthrough */ case '\0': setfline(atoi(s)-1); return p; default: goto bad_file; } bad_file: error("second parameter of #line is not a valid filename"); bad_line: error("first parameter of #line is not a positive integer"); } static char * pragma(char *s) { while (*s) ++s; return s; } static char * usererr(char *s) { fprintf(stderr, "%s:%u:error: #error %s\n", getfname(), getfline(), s); exit(-1); } char * preprocessor(char *p) { char *q; unsigned short n; static struct { char *name; char *(*fun)(char *); } *bp, cmds[] = { "define", define, "include", include, "line", line, "pragma", pragma, "error", usererr, NULL, NULL }; while (isspace(*p)) ++p; if (*p != '#') return p; for (++p; isspace(*p); ++p) /* nothing */; for (q = p; isalpha(*q); ++q) /* nothing */; n = q - p; while (isspace(*q)) ++q; for (bp = cmds; bp->name; ++bp) { if (strncmp(bp->name, p, n)) continue; q = (*bp->fun)(q); while (isspace(*q++)) /* nothing */; if (*q != '\0') error("trailing characters after preprocessor directive"); return NULL; } error("incorrect preprocessor directive"); }