git.ozlabs.org Git - ccan/blob - tools/ccanlint/tests/headers_idempotent.c

   1 #include <tools/ccanlint/ccanlint.h>
   2 #include <tools/tools.h>
   3 #include <ccan/talloc/talloc.h>
   4 #include <ccan/str/str.h>
   5 #include <sys/types.h>
   6 #include <sys/stat.h>
   7 #include <fcntl.h>
   8 #include <unistd.h>
   9 #include <limits.h>
  10 #include <errno.h>
  11 #include <stdlib.h>
  12 #include <stdio.h>
  13 #include <err.h>
  14 #include <string.h>
  15 #include <ctype.h>
  16
  17 static const char explain[]
  18 = "Headers usually start with the C preprocessor lines to prevent multiple\n"
  19   "inclusions.  These look like the following:\n"
  20   "#ifndef CCAN_<MODNAME>_H\n"
  21   "#define CCAN_<MODNAME>_H\n"
  22   "...\n"
  23   "#endif /* CCAN_<MODNAME>_H */\n";
  24
  25 static void fix_name(char *name)
  26 {
  27         unsigned int i;
  28
  29         for (i = 0; name[i]; i++) {
  30                 if (cisalnum(name[i]))
  31                         name[i] = toupper(name[i]);
  32                 else
  33                         name[i] = '_';
  34         }
  35 }
  36
  37 static void handle_idem(struct manifest *m, struct score *score)
  38 {
  39         struct file_error *e;
  40
  41         list_for_each(&score->per_file_errors, e, list) {
  42                 char *name, *q, *tmpname;
  43                 FILE *out;
  44                 unsigned int i;
  45
  46                 /* Main header gets CCAN_FOO_H, others CCAN_FOO_XXX_H */
  47                 if (strstarts(e->file->name, m->basename)
  48                     || strlen(e->file->name) == strlen(m->basename) + 2)
  49                         name = talloc_asprintf(score, "CCAN_%s_H", m->basename);
  50                 else
  51                         name = talloc_asprintf(score, "CCAN_%s_%s",
  52                                                m->basename, e->file->name);
  53                 fix_name(name);
  54
  55                 q = talloc_asprintf(score,
  56                             "Should I wrap %s in #ifndef/#define %s for you?",
  57                             e->file->name, name);
  58                 if (!ask(q))
  59                         continue;
  60
  61                 tmpname = maybe_temp_file(score, ".h", false, e->file->name);
  62                 out = fopen(tmpname, "w");
  63                 if (!out)
  64                         err(1, "Opening %s", tmpname);
  65                 if (fprintf(out, "#ifndef %s\n#define %s\n", name, name) < 0)
  66                         err(1, "Writing %s", tmpname);
  67
  68                 for (i = 0; i < e->file->num_lines; i++)
  69                         if (fprintf(out, "%s\n", e->file->lines[i]) < 0)
  70                                 err(1, "Writing %s", tmpname);
  71
  72                 if (fprintf(out, "#endif /* %s */\n", name) < 0)
  73                         err(1, "Writing %s", tmpname);
  74
  75                 if (fclose(out) != 0)
  76                         err(1, "Closing %s", tmpname);
  77
  78                 if (!move_file(tmpname, e->file->fullname))
  79                         err(1, "Moving %s to %s", tmpname, e->file->fullname);
  80         }
  81 }
  82
  83 static void check_idem(struct ccan_file *f, struct score *score)
  84 {
  85         struct line_info *line_info;
  86         unsigned int i, first_preproc_line;
  87         const char *line, *sym;
  88
  89         line_info = get_ccan_line_info(f);
  90         if (f->num_lines < 3)
  91                 /* FIXME: We assume small headers probably uninteresting. */
  92                 return;
  93
  94         for (i = 0; i < f->num_lines; i++) {
  95                 if (line_info[i].type == DOC_LINE
  96                     || line_info[i].type == COMMENT_LINE)
  97                         continue;
  98                 if (line_info[i].type == CODE_LINE) {
  99                         score_file_error(score, f, i+1,
 100                                          "Expect first non-comment line to be"
 101                                          " #ifndef.");
 102                         return;
 103                 } else if (line_info[i].type == PREPROC_LINE)
 104                         break;
 105         }
 106
 107         /* No code at all?  Don't complain. */
 108         if (i == f->num_lines)
 109                 return;
 110
 111         first_preproc_line = i;
 112         for (i = first_preproc_line+1; i < f->num_lines; i++) {
 113                 if (line_info[i].type == DOC_LINE
 114                     || line_info[i].type == COMMENT_LINE)
 115                         continue;
 116                 if (line_info[i].type == CODE_LINE) {
 117                         score_file_error(score, f, i+1,
 118                                          "Expect second non-comment line to be"
 119                                          " #define.");
 120                         return;
 121                 } else if (line_info[i].type == PREPROC_LINE)
 122                         break;
 123         }
 124
 125         /* No code at all?  Weird. */
 126         if (i == f->num_lines)
 127                 return;
 128
 129         /* We expect a condition on this line. */
 130         if (!line_info[i].cond) {
 131                 score_file_error(score, f, i+1, "Expected #ifndef");
 132                 return;
 133         }
 134
 135         line = f->lines[i];
 136
 137         /* We expect the condition to be ! IFDEF <symbol>. */
 138         if (line_info[i].cond->type != PP_COND_IFDEF
 139             || !line_info[i].cond->inverse) {
 140                 score_file_error(score, f, i+1, "Expected #ifndef");
 141                 return;
 142         }
 143
 144         /* And this to be #define <symbol> */
 145         if (!get_token(&line, "#"))
 146                 abort();
 147         if (!get_token(&line, "define")) {
 148                 score_file_error(score, f, i+1,
 149                                  "expected '#define %s'",
 150                                  line_info[i].cond->symbol);
 151                 return;
 152         }
 153         sym = get_symbol_token(f, &line);
 154         if (!sym || !streq(sym, line_info[i].cond->symbol)) {
 155                 score_file_error(score, f, i+1,
 156                                  "expected '#define %s'",
 157                                  line_info[i].cond->symbol);
 158                 return;
 159         }
 160
 161         /* Rest of code should all be covered by that conditional. */
 162         for (i++; i < f->num_lines; i++) {
 163                 unsigned int val = 0;
 164                 if (line_info[i].type == DOC_LINE
 165                     || line_info[i].type == COMMENT_LINE)
 166                         continue;
 167                 if (get_ccan_line_pp(line_info[i].cond, sym, &val, NULL)
 168                     != NOT_COMPILED) {
 169                         score_file_error(score, f, i+1, "code outside"
 170                                          " idempotent region");
 171                         return;
 172                 }
 173         }
 174 }
 175
 176 static void check_idempotent(struct manifest *m,
 177                              bool keep,
 178                              unsigned int *timeleft, struct score *score)
 179 {
 180         struct ccan_file *f;
 181
 182         /* We don't fail ccanlint for this. */
 183         score->pass = true;
 184
 185         list_for_each(&m->h_files, f, list) {
 186                 check_idem(f, score);
 187         }
 188         if (!score->error) {
 189                 score->score = score->total;
 190         }
 191 }
 192
 193 struct ccanlint headers_idempotent = {
 194         .key = "headers_idempotent",
 195         .name = "Module headers are #ifndef/#define wrapped",
 196         .check = check_idempotent,
 197         .handle = handle_idem,
 198         .needs = ""
 199 };
 200
 201 REGISTER_TEST(headers_idempotent);