ccanlint: with -vv, give details on attempts to compile examples.
authorRusty Russell <rusty@rustcorp.com.au>
Wed, 3 Nov 2010 12:51:18 +0000 (23:21 +1030)
committerRusty Russell <rusty@rustcorp.com.au>
Wed, 3 Nov 2010 12:51:18 +0000 (23:21 +1030)
The heuristics can be hinky, so tell people what we're doing.

tools/ccanlint/tests/examples_compile.c

index 4f2d2c8a99189b058e7610b101cbcd264dca186c..82b479620c614ba6c1e7d995003b60bdd96a0864 100644 (file)
@@ -132,12 +132,12 @@ struct score {
        char *errors;
 };
 
-static char *start_main(char *ret)
+static char *start_main(char *ret, const char *why)
 {
        return talloc_asprintf_append(ret,
-                                     "/* Fake function wrapper inserted */\n"
-                                     "int main(int argc, char *argv[])\n"
-                                     "{\n");
+             "/* The example %s, so fake function wrapper inserted */\n"
+             "int main(int argc, char *argv[])\n"
+             "{\n", why);
 }
 
 /* We only handle simple function definitions here. */
@@ -177,7 +177,7 @@ static void strip_leading_whitespace(char **lines)
                        lines[i] += min_span;
 }
 
-static bool looks_internal(char **lines)
+static bool looks_internal(char **lines, char **why)
 {
        unsigned int i;
        bool last_ended = true; /* Did last line finish a statement? */
@@ -191,30 +191,46 @@ static bool looks_internal(char **lines)
                        continue;
 
                /* The winners. */
-               if (strstarts(line, "if") && len == 2)
+               if (strstarts(line, "if") && len == 2) {
+                       *why = "starts with if";
                        return true;
-               if (strstarts(line, "for") && len == 3)
+               }
+               if (strstarts(line, "for") && len == 3) {
+                       *why = "starts with for";
                        return true;
-               if (strstarts(line, "while") && len == 5)
+               }
+               if (strstarts(line, "while") && len == 5) {
+                       *why = "starts with while";
                        return true;
-               if (strstarts(line, "do") && len == 2)
+               }
+               if (strstarts(line, "do") && len == 2) {
+                       *why = "starts with do";
                        return true;
+               }
 
                /* The losers. */
-               if (strstarts(line, "#include"))
+               if (strstarts(line, "#include")) {
+                       *why = "starts with #include";
                        return false;
+               }
 
                if (last_ended && strchr(line, '(')) {
-                       if (strstarts(line, "static"))
+                       if (strstarts(line, "static")) {
+                               *why = "starts with static and contains (";
                                return false;
-                       if (strends(line, ")"))
+                       }
+                       if (strends(line, ")")) {
+                               *why = "contains ( and ends with )";
                                return false;
+                       }
                }
 
                /* Single identifier then operator == inside function. */
                if (last_ended && len
-                   && ispunct(line[len+strspn(line+len, " ")]))
+                   && ispunct(line[len+strspn(line+len, " ")])) {
+                       *why = "starts with identifier then punctuation";
                        return true;
+               }
 
                last_ended = (strends(line, "}")
                              || strends(line, ";")
@@ -222,6 +238,7 @@ static bool looks_internal(char **lines)
        }
 
        /* No idea... Say yes? */
+       *why = "gave no clues";
        return true;
 }
 
@@ -230,24 +247,35 @@ static char **combine(const void *ctx, char **lines, char **prev)
 {
        unsigned int i, lines_total, prev_total, count;
        char **ret;
+       const char *reasoning;
+       char *why = NULL;
 
        if (!prev)
                return NULL;
 
        /* If it looks internal, put prev at start. */
-       if (looks_internal(lines)) {
+       if (looks_internal(lines, &why)) {
                count = 0;
+               reasoning = "seemed to belong inside a function";
        } else {
                /* Try inserting in first elided position */
                for (count = 0; lines[count]; count++) {
                        if (strcmp(lines[count], "...") == 0)
                                break;
                }
-               if (!lines[count])
+               if (!lines[count]) {
                        /* Try at start anyway? */
                        count = 0;
-               else
+                       reasoning = "didn't seem to belong inside"
+                               " a function, so we prepended the previous"
+                               " example";
+               } else {
+                       reasoning = "didn't seem to belong inside"
+                               " a function, so we put the previous example"
+                               " at the first ...";
+
                        count++;
+               }
        }
 
        for (i = 0; lines[i]; i++);
@@ -256,17 +284,19 @@ static char **combine(const void *ctx, char **lines, char **prev)
        for (i = 0; prev[i]; i++);
        prev_total = i;
 
-       ret = talloc_array(ctx, char *, lines_total + prev_total + 1);
-       memcpy(ret, lines, count * sizeof(ret[0]));
-       memcpy(ret + count, prev, prev_total * sizeof(ret[0]));
-       memcpy(ret + count + prev_total, lines + count,
+       ret = talloc_array(ctx, char *, 1 +lines_total + prev_total + 1);
+       ret[0] = talloc_asprintf(ret, "/* The example %s, thus %s */\n",
+                                why, reasoning);
+       memcpy(ret+1, lines, count * sizeof(ret[0]));
+       memcpy(ret+1 + count, prev, prev_total * sizeof(ret[0]));
+       memcpy(ret+1 + count + prev_total, lines + count,
               (lines_total - count + 1) * sizeof(ret[0]));
        return ret;
 }
 
 static char *mangle(struct manifest *m, char **lines)
 {
-       char *ret, *use_funcs = NULL;
+       char *ret, *use_funcs = NULL, *why;
        bool in_function = false, fake_function = false, has_main = false;
        unsigned int i;
 
@@ -294,13 +324,16 @@ static char *mangle(struct manifest *m, char **lines)
                                     "extern char somestring[];\n"
                                     "char somestring[] = \"hello world\";\n");
 
-       if (looks_internal(lines)) {
+       if (looks_internal(lines, &why)) {
                /* Wrap it all in main(). */
-               ret = start_main(ret);
+               ret = start_main(ret, why);
                fake_function = true;
                in_function = true;
                has_main = true;
-       }
+       } else
+               ret = talloc_asprintf_append(ret,
+                            "/* The example %s, so didn't wrap in main() */\n",
+                                    why);
 
        /* Primitive, very primitive. */
        for (i = 0; lines[i]; i++) {
@@ -327,9 +360,9 @@ static char *mangle(struct manifest *m, char **lines)
                /* ... means elided code. */
                if (strcmp(lines[i], "...") == 0) {
                        if (!in_function && !has_main
-                           && looks_internal(lines + i + 1)) {
+                           && looks_internal(lines + i + 1, &why)) {
                                /* This implies we start a function here. */
-                               ret = start_main(ret);
+                               ret = start_main(ret, why);
                                has_main = true;
                                fake_function = true;
                                in_function = true;
@@ -341,14 +374,18 @@ static char *mangle(struct manifest *m, char **lines)
                ret = talloc_asprintf_append(ret, "%s\n", lines[i]);
        }
 
-       /* Need a main to link successfully. */
        if (!has_main) {
-               ret = talloc_asprintf_append(ret, "int main(void)\n{\n");
+               ret = talloc_asprintf_append(ret,
+                            "/* Need a main to link successfully. */\n"
+                            "int main(void)\n{\n");
                fake_function = true;
        }
 
-       /* Get rid of unused warnings by printing addresses of static funcs. */
        if (use_funcs) {
+               ret = talloc_asprintf_append(ret,
+                                            "/* Get rid of unused warnings"
+                                            " by printing addresses of"
+                                            " static funcs. */");
                if (!fake_function) {
                        ret = talloc_asprintf_append(ret,
                                                     "int use_funcs(void);\n"
@@ -400,14 +437,15 @@ static void *build_examples(struct manifest *m, bool keep,
 {
        struct ccan_file *i;
        struct score *score = talloc(m, struct score);
-       struct ccan_file *mangle;
        char **prev = NULL;
 
        score->score = 0;
-       score->errors = NULL;
+       score->errors = talloc_strdup(score, "");
 
+       examples_compile.total_score = 0;
        list_for_each(&m->examples, i, list) {
-               char *ret;
+               char *ret, *ret1 = NULL, *ret2;
+               struct ccan_file *mangle1 = NULL, *mangle2;
 
                examples_compile.total_score++;
                /* Simplify our dumb parsing. */
@@ -422,11 +460,10 @@ static void *build_examples(struct manifest *m, bool keep,
                /* Try combining with previous (successful) example... */
                if (prev) {
                        char **new = combine(i, get_ccan_file_lines(i), prev);
-                       talloc_free(ret);
 
-                       mangle = mangle_example(m, i, new, keep);
-                       ret = compile(score, m, mangle, keep);
-                       if (!ret) {
+                       mangle1 = mangle_example(m, i, new, keep);
+                       ret1 = compile(score, m, mangle1, keep);
+                       if (!ret1) {
                                prev = new;
                                score->score++;
                                continue;
@@ -434,22 +471,38 @@ static void *build_examples(struct manifest *m, bool keep,
                }
 
                /* Try standalone. */
-               talloc_free(ret);
-               mangle = mangle_example(m, i, get_ccan_file_lines(i), keep);
-               ret = compile(score, m, mangle, keep);
-               if (!ret) {
+               mangle2 = mangle_example(m, i, get_ccan_file_lines(i), keep);
+               ret2 = compile(score, m, mangle2, keep);
+               if (!ret2) {
                        prev = get_ccan_file_lines(i);
                        score->score++;
                        continue;
                }
 
-               if (!score->errors)
-                       score->errors = ret;
-               else {
-                       score->errors = talloc_append_string(score->errors,
-                                                            ret);
-                       talloc_free(ret);
+               score->errors = talloc_asprintf_append(score->errors,
+                                      "%s: tried standalone example:\n"
+                                      "%s\n"
+                                      "Errors: %s\n\n",
+                                      i->name,
+                                      get_ccan_file_contents(i),
+                                      ret);
+               if (mangle1) {
+                       score->errors = talloc_asprintf_append(score->errors,
+                                              "%s: tried combining with"
+                                              " previous example:\n"
+                                              "%s\n"
+                                              "Errors: %s\n\n",
+                                              i->name,
+                                              get_ccan_file_contents(mangle1),
+                                              ret1);
                }
+               score->errors = talloc_asprintf_append(score->errors,
+                                      "%s: tried adding headers, wrappers:\n"
+                                      "%s\n"
+                                      "Errors: %s\n\n",
+                                      i->name,
+                                      get_ccan_file_contents(mangle2),
+                                      ret2);
                /* This didn't work, so not a candidate for combining. */
                prev = NULL;
        }
@@ -475,6 +528,7 @@ struct ccanlint examples_compile = {
        .key = "examples-compile",
        .name = "Module examples compile",
        .score = score_examples,
+       .total_score = 3, /* This gets changed to # examples, if they exist */
        .check = build_examples,
        .describe = describe,
        .can_run = can_run,