git.ozlabs.org Git - ccan/blob - tools/read_config_header.c

   1 #include <ccan/err/err.h>
   2 #include <ccan/str/str.h>
   3 #include <ccan/tal/path/path.h>
   4 #include "read_config_header.h"
   5 #include "tools.h"
   6 #include <string.h>
   7
   8 /* Get an identifier token. */
   9 char *get_symbol_token(void *ctx, const char **line)
  10 {
  11         unsigned int toklen;
  12         char *ret;
  13
  14         *line += strspn(*line, " \t");
  15         toklen = strspn(*line, IDENT_CHARS);
  16         if (!toklen)
  17                 return NULL;
  18         ret = tal_strndup(ctx, *line, toklen);
  19         *line += toklen;
  20         return ret;
  21 }
  22
  23 /* Get token if it's equal to token. */
  24 bool get_token(const char **line, const char *token)
  25 {
  26         unsigned int toklen;
  27
  28         *line += strspn(*line, " \t");
  29         if (cisalnum(token[0]) || token[0] == '_')
  30                 toklen = strspn(*line, IDENT_CHARS);
  31         else {
  32                 /* FIXME: real tokenizer handles ++ and other multi-chars.  */
  33                 toklen = strlen(token);
  34         }
  35
  36         if (toklen == strlen(token) && !strncmp(*line, token, toklen)) {
  37                 *line += toklen;
  38                 return true;
  39         }
  40         return false;
  41 }
  42
  43 static char *demangle_string(char *string)
  44 {
  45         unsigned int i;
  46         const char mapfrom[] = "abfnrtv";
  47         const char mapto[] = "\a\b\f\n\r\t\v";
  48
  49         if (!strchr(string, '"'))
  50                 return NULL;
  51         string = strchr(string, '"') + 1;
  52         if (!strrchr(string, '"'))
  53                 return NULL;
  54         *strrchr(string, '"') = '\0';
  55
  56         for (i = 0; i < strlen(string); i++) {
  57                 if (string[i] == '\\') {
  58                         char repl;
  59                         unsigned len = 0;
  60                         const char *p = strchr(mapfrom, string[i+1]);
  61                         if (p) {
  62                                 repl = mapto[p - mapfrom];
  63                                 len = 1;
  64                         } else if (strlen(string+i+1) >= 3) {
  65                                 if (string[i+1] == 'x') {
  66                                         repl = (string[i+2]-'0')*16
  67                                                 + string[i+3]-'0';
  68                                         len = 3;
  69                                 } else if (cisdigit(string[i+1])) {
  70                                         repl = (string[i+2]-'0')*8*8
  71                                                 + (string[i+3]-'0')*8
  72                                                 + (string[i+4]-'0');
  73                                         len = 3;
  74                                 }
  75                         }
  76                         if (len == 0) {
  77                                 repl = string[i+1];
  78                                 len = 1;
  79                         }
  80
  81                         string[i] = repl;
  82                         memmove(string + i + 1, string + i + len + 1,
  83                                 strlen(string + i + len + 1) + 1);
  84                 }
  85         }
  86
  87         return string;
  88 }
  89
  90 char *read_config_header(const char *ccan_dir, bool verbose)
  91 {
  92         char *fname = path_join(NULL, ccan_dir, "config.h");
  93         char **lines;
  94         unsigned int i;
  95         char *config_header;
  96
  97         config_header = tal_grab_file(NULL, fname, NULL);
  98         tal_free(fname);
  99
 100         if (!config_header)
 101                 return NULL;
 102
 103         lines = tal_strsplit(config_header, config_header, "\n", STR_EMPTY_OK);
 104         for (i = 0; i < tal_count(lines) - 1; i++) {
 105                 char *sym;
 106                 const char **line = (const char **)&lines[i];
 107
 108                 if (!get_token(line, "#"))
 109                         continue;
 110                 if (!get_token(line, "define"))
 111                         continue;
 112                 sym = get_symbol_token(lines, line);
 113                 if (streq(sym, "CCAN_COMPILER")) {
 114                         compiler = demangle_string(lines[i]);
 115                         if (!compiler)
 116                                 errx(1, "%s:%u:could not parse CCAN_COMPILER",
 117                                      fname, i+1);
 118                         if (verbose)
 119                                 printf("%s: compiler set to '%s'\n",
 120                                        fname, compiler);
 121                 } else if (streq(sym, "CCAN_CFLAGS")) {
 122                         cflags = demangle_string(lines[i]);
 123                         if (!cflags)
 124                                 errx(1, "%s:%u:could not parse CCAN_CFLAGS",
 125                                      fname, i+1);
 126                         if (verbose)
 127                                 printf("%s: compiler flags set to '%s'\n",
 128                                        fname, cflags);
 129                 }
 130         }
 131         return config_header;
 132 }