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 "read_config_header.h"
   4 #include "tools.h"
   5 #include <string.h>
   6
   7 /* Get an identifier token. */
   8 char *get_symbol_token(void *ctx, const char **line)
   9 {
  10         unsigned int toklen;
  11         char *ret;
  12
  13         *line += strspn(*line, " \t");
  14         toklen = strspn(*line, IDENT_CHARS);
  15         if (!toklen)
  16                 return NULL;
  17         ret = tal_strndup(ctx, *line, toklen);
  18         *line += toklen;
  19         return ret;
  20 }
  21
  22 /* Get token if it's equal to token. */
  23 bool get_token(const char **line, const char *token)
  24 {
  25         unsigned int toklen;
  26
  27         *line += strspn(*line, " \t");
  28         if (cisalnum(token[0]) || token[0] == '_')
  29                 toklen = strspn(*line, IDENT_CHARS);
  30         else {
  31                 /* FIXME: real tokenizer handles ++ and other multi-chars.  */
  32                 toklen = strlen(token);
  33         }
  34
  35         if (toklen == strlen(token) && !strncmp(*line, token, toklen)) {
  36                 *line += toklen;
  37                 return true;
  38         }
  39         return false;
  40 }
  41
  42 static char *demangle_string(char *string)
  43 {
  44         unsigned int i;
  45         const char mapfrom[] = "abfnrtv";
  46         const char mapto[] = "\a\b\f\n\r\t\v";
  47
  48         if (!strchr(string, '"'))
  49                 return NULL;
  50         string = strchr(string, '"') + 1;
  51         if (!strrchr(string, '"'))
  52                 return NULL;
  53         *strrchr(string, '"') = '\0';
  54
  55         for (i = 0; i < strlen(string); i++) {
  56                 if (string[i] == '\\') {
  57                         char repl;
  58                         unsigned len = 0;
  59                         const char *p = strchr(mapfrom, string[i+1]);
  60                         if (p) {
  61                                 repl = mapto[p - mapfrom];
  62                                 len = 1;
  63                         } else if (strlen(string+i+1) >= 3) {
  64                                 if (string[i+1] == 'x') {
  65                                         repl = (string[i+2]-'0')*16
  66                                                 + string[i+3]-'0';
  67                                         len = 3;
  68                                 } else if (cisdigit(string[i+1])) {
  69                                         repl = (string[i+2]-'0')*8*8
  70                                                 + (string[i+3]-'0')*8
  71                                                 + (string[i+4]-'0');
  72                                         len = 3;
  73                                 }
  74                         }
  75                         if (len == 0) {
  76                                 repl = string[i+1];
  77                                 len = 1;
  78                         }
  79
  80                         string[i] = repl;
  81                         memmove(string + i + 1, string + i + len + 1,
  82                                 strlen(string + i + len + 1) + 1);
  83                 }
  84         }
  85
  86         return string;
  87 }
  88
  89 char *read_config_header(const char *ccan_dir,
  90                          const char **compiler, const char **cflags,
  91                          bool verbose)
  92 {
  93         char *fname = tal_fmt(NULL, "%s/config.h", ccan_dir);
  94         char **lines;
  95         unsigned int i;
  96         char *config_header;
  97
  98         config_header = tal_grab_file(NULL, fname, NULL);
  99         tal_free(fname);
 100
 101         if (!config_header)
 102                 goto out;
 103
 104         lines = tal_strsplit(config_header, config_header, "\n", STR_EMPTY_OK);
 105         for (i = 0; i < tal_count(lines) - 1; i++) {
 106                 char *sym;
 107                 const char **line = (const char **)&lines[i];
 108
 109                 if (!get_token(line, "#"))
 110                         continue;
 111                 if (!get_token(line, "define"))
 112                         continue;
 113                 sym = get_symbol_token(lines, line);
 114                 if (streq(sym, "CCAN_COMPILER") && !compiler) {
 115                         *compiler = demangle_string(lines[i]);
 116                         if (!*compiler)
 117                                 errx(1, "%s:%u:could not parse CCAN_COMPILER",
 118                                      fname, i+1);
 119                         if (verbose)
 120                                 printf("%s: compiler set to '%s'\n",
 121                                        fname, *compiler);
 122                 } else if (streq(sym, "CCAN_CFLAGS") && !cflags) {
 123                         *cflags = demangle_string(lines[i]);
 124                         if (!*cflags)
 125                                 errx(1, "%s:%u:could not parse CCAN_CFLAGS",
 126                                      fname, i+1);
 127                         if (verbose)
 128                                 printf("%s: compiler flags set to '%s'\n",
 129                                        fname, *cflags);
 130                 }
 131         }
 132
 133 out:
 134         if (!*compiler)
 135                 *compiler = CCAN_COMPILER;
 136         if (!*cflags)
 137                 *cflags = CCAN_CFLAGS;
 138
 139         return config_header;
 140 }