X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=tools%2Fccanlint%2Ftests%2Fidempotent.c;fp=tools%2Fccanlint%2Ftests%2Fidempotent.c;h=0aa7d8b3ae22c5ad741187bb3b7905abefe5e63b;hp=0000000000000000000000000000000000000000;hb=8f61c0bccb152b2365baf70deac1e59264d7feb7;hpb=15290c3feb9b61967311659a865fb3b5d05b1a49

diff --git a/tools/ccanlint/tests/idempotent.c b/tools/ccanlint/tests/idempotent.c
new file mode 100644
index 00000000..0aa7d8b3
--- /dev/null
+++ b/tools/ccanlint/tests/idempotent.c
@@ -0,0 +1,139 @@
+#include <tools/ccanlint/ccanlint.h>
+#include <tools/tools.h>
+#include <ccan/talloc/talloc.h>
+#include <ccan/str/str.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <limits.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <err.h>
+#include <string.h>
+#include <ctype.h>
+
+static const char explain[] 
+= "Headers usually start with the C preprocessor lines to prevent multiple\n"
+  "inclusions.  These look like the following:\n"
+  "#ifndef MY_HEADER_H\n"
+  "#define MY_HEADER_H\n"
+  "...\n"
+  "#endif /* MY_HEADER_H */\n";
+
+static char *report_idem(struct ccan_file *f, char *sofar)
+{
+	struct line_info *line_info;
+	unsigned int i, first_preproc_line;
+	const char *line, *sym;
+
+	line_info = get_ccan_line_info(f);
+	if (f->num_lines < 3)
+		/* FIXME: We assume small headers probably uninteresting. */
+		return sofar;
+
+	for (i = 0; i < f->num_lines; i++) {
+		if (line_info[i].type == DOC_LINE
+		    || line_info[i].type == COMMENT_LINE)
+			continue;
+		if (line_info[i].type == CODE_LINE)
+			return talloc_asprintf_append(sofar,
+			      "%s:%u:expect first non-comment line to be #ifndef.\n", f->name, i+1);
+		else if (line_info[i].type == PREPROC_LINE)
+			break;
+	}
+
+	/* No code at all?  Don't complain. */
+	if (i == f->num_lines)
+		return sofar;
+
+	first_preproc_line = i;
+	for (i = first_preproc_line+1; i < f->num_lines; i++) {
+		if (line_info[i].type == DOC_LINE
+		    || line_info[i].type == COMMENT_LINE)
+			continue;
+		if (line_info[i].type == CODE_LINE)
+			return talloc_asprintf_append(sofar,
+			      "%s:%u:expect second line to be #define.\n", f->name, i+1);
+		else if (line_info[i].type == PREPROC_LINE)
+			break;
+	}
+
+	/* No code at all?  Weird. */
+	if (i == f->num_lines)
+		return sofar;
+
+	/* We expect a condition on this line. */
+	if (!line_info[i].cond) {
+		return talloc_asprintf_append(sofar,
+					      "%s:%u:expected #ifndef.\n",
+					      f->name, first_preproc_line+1);
+	}
+
+	line = f->lines[i];
+
+	/* We expect the condition to be ! IFDEF <symbol>. */
+	if (line_info[i].cond->type != PP_COND_IFDEF
+	    || !line_info[i].cond->inverse) {
+		return talloc_asprintf_append(sofar,
+					      "%s:%u:expected #ifndef.\n",
+					      f->name, first_preproc_line+1);
+	}
+
+	/* And this to be #define <symbol> */
+	if (!get_token(&line, "#"))
+		abort();
+	if (!get_token(&line, "define")) {
+		return talloc_asprintf_append(sofar,
+			      "%s:%u:expected '#define %s'.\n",
+			      f->name, i+1, line_info[i].cond->symbol);
+	}
+	sym = get_symbol_token(f, &line);
+	if (!sym || !streq(sym, line_info[i].cond->symbol)) {
+		return talloc_asprintf_append(sofar,
+			      "%s:%u:expected '#define %s'.\n",
+			      f->name, i+1, line_info[i].cond->symbol);
+	}
+
+	/* Rest of code should all be covered by that conditional. */
+	for (i++; i < f->num_lines; i++) {
+		unsigned int val = 0;
+		if (line_info[i].type == DOC_LINE
+		    || line_info[i].type == COMMENT_LINE)
+			continue;
+		if (get_ccan_line_pp(line_info[i].cond, sym, &val, NULL)
+		    != NOT_COMPILED)
+			return talloc_asprintf_append(sofar,
+			      "%s:%u:code outside idempotent region.\n",
+			      f->name, i+1);
+	}
+
+	return sofar;
+}
+
+static void *check_idempotent(struct manifest *m)
+{
+	struct ccan_file *f;
+	char *report = NULL;
+
+	list_for_each(&m->h_files, f, list)
+		report = report_idem(f, report);
+
+	return report;
+}
+
+static const char *describe_idempotent(struct manifest *m, void *check_result)
+{
+	return talloc_asprintf(check_result, 
+			       "Some headers not idempotent:\n"
+			       "%s\n%s", (char *)check_result,
+			       explain);
+}
+
+struct ccanlint idempotent = {
+	.name = "Headers are #ifndef/#define idempotent wrapped",
+	.total_score = 1,
+	.check = check_idempotent,
+	.describe = describe_idempotent,
+};