Remove fsm.opt and split print hooks from options.

The important part of the diff here is just:
```diff
--- a/src/libfsm/internal.h
+++ b/src/libfsm/internal.h
@@ -11,7 +11,6 @@
 #include <stdlib.h>

 #include <fsm/fsm.h>
-#include <fsm/options.h>

 #include <adt/common.h>

@@ -76,7 +75,6 @@ struct fsm {

        struct fsm_capture_info *capture_info;
        struct endid_info *endid_info;
-       const struct fsm_options *opt;
 };
```

Everything else is fallout from not needing to pass around the options struct. This leaves the options struct only used for the print routines.

fuzz/target.c

@@ -75,8 +75,6 @@ scanner_next(void *opaque)
 }
 #endif
 
-static const struct fsm_options opt;
-
 static struct fsm *
 build(const char *pattern)
 {
@@ -95,7 +93,7 @@ build(const char *pattern)
 	};
 
 	time_get(&pre);
-	fsm = re_comp(RE_PCRE, scanner_next, &s, NULL, &opt, RE_MULTI, &err);
+	fsm = re_comp(RE_PCRE, scanner_next, &s, NULL, RE_MULTI, &err);
 	time_get(&post);
 	delta_usec = time_diff_usec(&pre, &post);
 	total_usec += delta_usec;
@@ -133,24 +131,28 @@ build(const char *pattern)
 }
 
 static int
-codegen(const struct fsm *fsm)
+codegen(const struct fsm *fsm, enum fsm_io io_mode)
 {
+	const struct fsm_options opt = {
+		.io = io_mode,
+	};
+
 	FILE *dev_null = fopen("/dev/null", "w");
 	assert(dev_null != NULL);
-	fsm_print(dev_null, fsm, FSM_PRINT_C);
+	fsm_print(dev_null, fsm, &opt, NULL, FSM_PRINT_C);
 	fclose(dev_null);
 	return 1;
 }
 
 static int
-build_and_codegen(const char *pattern)
+build_and_codegen(const char *pattern, enum fsm_io io_mode)
 {
 	struct fsm *fsm = build(pattern);
 	if (fsm == NULL) {
 		return EXIT_SUCCESS;
 	}
 
-	if (!codegen(fsm)) {
+	if (!codegen(fsm, io_mode)) {
 		return EXIT_SUCCESS;
 	}
 
@@ -176,7 +178,7 @@ shuffle_minimise(const char *pattern)
 		.offset = 0
 	};
 
-	fsm = re_comp(RE_PCRE, scanner_next, &s, NULL, &opt, RE_MULTI, &err);
+	fsm = re_comp(RE_PCRE, scanner_next, &s, NULL, RE_MULTI, &err);
 
 	if (fsm == NULL) {
 		/* ignore invalid regexp syntax, etc. */
@@ -245,14 +247,14 @@ shuffle_minimise(const char *pattern)
 			    __func__, s_i, pattern, expected_state_count, cp_state_count);
 
 			fprintf(stderr, "== original input:\n");
-			fsm_print(stderr, fsm, FSM_PRINT_FSM);
+			fsm_print(stderr, fsm, NULL, NULL, FSM_PRINT_FSM);
 
 
 			fprintf(stderr, "== expected:\n");
-			fsm_print(stderr, oracle_min, FSM_PRINT_FSM);
+			fsm_print(stderr, oracle_min, NULL, NULL, FSM_PRINT_FSM);
 
 			fprintf(stderr, "== got:\n");
-			fsm_print(stderr, cp, FSM_PRINT_FSM);
+			fsm_print(stderr, cp, NULL, NULL, FSM_PRINT_FSM);
 
 			fsm_free(cp);
 			fsm_free(oracle_min);
@@ -287,7 +289,7 @@ fuzz_all_print_functions(FILE *f, const char *pattern, bool det, bool min, const
 		.io = io_mode,
 	};
 
-	fsm = re_comp(RE_PCRE, scanner_next, &s, NULL, &opt, RE_MULTI, &err);
+	fsm = re_comp(RE_PCRE, scanner_next, &s, NULL, RE_MULTI, &err);
 	if (fsm == NULL) {
 		/* ignore invalid regexp syntax, etc. */
 		return EXIT_SUCCESS;
@@ -313,28 +315,28 @@ fuzz_all_print_functions(FILE *f, const char *pattern, bool det, bool min, const
 	/* see if this triggers any asserts */
 	int r = 0;
 
-	r |= fsm_print(f, fsm, FSM_PRINT_AMD64_ATT);
-	r |= fsm_print(f, fsm, FSM_PRINT_AMD64_GO);
-	r |= fsm_print(f, fsm, FSM_PRINT_AMD64_NASM);
-
-	r |= fsm_print(f, fsm, FSM_PRINT_API);
-	r |= fsm_print(f, fsm, FSM_PRINT_AWK);
-	r |= fsm_print(f, fsm, FSM_PRINT_C);
-	r |= fsm_print(f, fsm, FSM_PRINT_DOT);
-	r |= fsm_print(f, fsm, FSM_PRINT_FSM);
-	r |= fsm_print(f, fsm, FSM_PRINT_GO);
-	r |= fsm_print(f, fsm, FSM_PRINT_IR);
-	r |= fsm_print(f, fsm, FSM_PRINT_IRJSON);
-	r |= fsm_print(f, fsm, FSM_PRINT_JSON);
-	r |= fsm_print(f, fsm, FSM_PRINT_LLVM);
-	r |= fsm_print(f, fsm, FSM_PRINT_RUST);
-	r |= fsm_print(f, fsm, FSM_PRINT_SH);
-	r |= fsm_print(f, fsm, FSM_PRINT_VMC);
-	r |= fsm_print(f, fsm, FSM_PRINT_VMDOT);
-
-	r |= fsm_print(f, fsm, FSM_PRINT_VMOPS_C);
-	r |= fsm_print(f, fsm, FSM_PRINT_VMOPS_H);
-	r |= fsm_print(f, fsm, FSM_PRINT_VMOPS_MAIN);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_AMD64_ATT);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_AMD64_GO);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_AMD64_NASM);
+
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_API);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_AWK);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_C);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_DOT);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_FSM);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_GO);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_IR);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_IRJSON);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_JSON);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_LLVM);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_RUST);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_SH);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_VMC);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_VMDOT);
+
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_VMOPS_C);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_VMOPS_H);
+	r |= fsm_print(f, fsm, &opt, NULL, FSM_PRINT_VMOPS_MAIN);
 
 	assert(r == 0 || errno != 0);
 
@@ -380,8 +382,12 @@ harness_fuzzer_target(const uint8_t *data, size_t size)
 	const char *pattern = (const char *)data_buf;
 
 	switch (get_run_mode()) {
-	case MODE_DEFAULT:
-		return build_and_codegen(pattern);
+	case MODE_DEFAULT: {
+		const uint8_t b0 = data_buf[0];
+		const enum fsm_io io_mode = (b0 >> 2) % 3;
+
+		return build_and_codegen(pattern, io_mode);
+	}
 
 	case MODE_SHUFFLE_MINIMISE:
 		return shuffle_minimise(pattern);

include/fsm/fsm.h

@@ -11,7 +11,6 @@
 
 struct fsm;
 struct fsm_alloc;
-struct fsm_options;
 struct path; /* XXX */
 struct fsm_capture;
 struct fsm_combine_info;
@@ -35,14 +34,12 @@ typedef unsigned int fsm_end_id_t;
  * from fsm_new() is expected to be passed as the "fsm" argument to the
  * functions in this API.
  *
- * An options pointer may be passed for control over various details of
- * FSM construction and output. This may be NULL, in which case default
- * options are used.
+ * An fsm_alloc pointer may be passed for callbacks on memory allocation.
+ * This may be NULL, in which case the default libc functions are used.
  * When non-NULL, the storage pointed to must remain extant until fsm_free().
  *
  * Returns NULL on error; see errno.
  * TODO: perhaps automatically create a start state, and never have an empty FSM
- * TODO: also fsm_parse should create an FSM, not add into an existing one
  */
 struct fsm *
 fsm_new(const struct fsm_alloc *alloc);
@@ -69,14 +66,6 @@ fsm_free(struct fsm *fsm);
 struct fsm *
 fsm_clone(const struct fsm *fsm);
 
-/* Returns the options of an FSM */
-const struct fsm_options *
-fsm_getoptions(const struct fsm *fsm);
-
-/* Sets the options of an FSM */
-void
-fsm_setoptions(struct fsm *fsm, const struct fsm_options *opts);
-
 /*
  * Copy the contents of src over dst, and free src.
  *

include/fsm/options.h

@@ -7,11 +7,6 @@
 #ifndef FSM_OPTIONS_H
 #define FSM_OPTIONS_H
 
-#include <stdio.h>
-
-struct fsm;
-struct fsm_state;
-
 enum fsm_io {
 	FSM_IO_GETC,
 	FSM_IO_STR,
@@ -28,6 +23,10 @@ enum fsm_ambig {
 	AMBIG_SINGLE   = AMBIG_ERROR | AMBIG_EARLIEST
 };
 
+/*
+ * Print options.
+ * This is separate to <fsm/print.h> because we also borrow it for libre.
+ */
 struct fsm_options {
 	/* boolean: true indicates to omit names for states in output */
 	unsigned int anonymous_states:1;
@@ -73,38 +72,6 @@ struct fsm_options {
 
 	/* the name of the enclosing package; NULL to use `prefix` (default). */
 	const char *package_prefix;
-
-	/*
-	 * Hooks to override generated code. These give an oportunity to
-	 * emit application-specific constructs, especially based on ids
-	 * attached to end states.
-	 *
-	 * These hooks are optional, and default to whatever makes sense
-	 * for the language.
-	 *
-	 * Placement in the output stream depends on the format.
-	 * This replaces an entire "return xyz;" statement for C-like formats,
-	 * but appends extra information for others.
-	 */
-	struct fsm_hooks {
-		/* character pointer, for C code fragment output. NULL for the default. */
-		const char *cp;
-
-		int (*args)(FILE *, const struct fsm_options *opt,
-			void *leaf_opaque);
-
-		/*
-		 * ids[] is sorted and does not have duplicates.
-		 */
-		int (*accept)(FILE *, const struct fsm_options *opt,
-			const fsm_end_id_t *ids, size_t count,
-			void *leaf_opaque);
-
-		int (*reject)(FILE *, const struct fsm_options *opt,
-			void *leaf_opaque);
-
-		void *hook_opaque;
-	} hooks;
 };
 
 #endif

include/fsm/print.h

@@ -7,9 +7,8 @@
 #ifndef FSM_PRINT_H
 #define FSM_PRINT_H
 
-#include <stdio.h>
-
 struct fsm;
+struct fsm_options;
 
 enum fsm_print_lang {
 	FSM_PRINT_NONE,       /* No output */
@@ -38,6 +37,38 @@ enum fsm_print_lang {
 	FSM_PRINT_VMOPS_MAIN
 };
 
+/*
+ * Hooks to override generated code. These give an oportunity to
+ * emit application-specific constructs, especially based on ids
+ * attached to end states.
+ *
+ * These hooks are optional, and default to whatever makes sense
+ * for the language.
+ *
+ * Placement in the output stream depends on the format.
+ * This replaces an entire "return xyz;" statement for C-like formats,
+ * but appends extra information for others.
+ */
+struct fsm_hooks {
+	/* character pointer, for C code fragment output. NULL for the default. */
+	const char *cp;
+
+	int (*args)(FILE *, const struct fsm_options *opt,
+		void *leaf_opaque, void *hook_opaque);
+
+	/*
+	 * ids[] is sorted and does not have duplicates.
+	 */
+	int (*accept)(FILE *, const struct fsm_options *opt,
+		const fsm_end_id_t *ids, size_t count,
+		void *leaf_opaque, void *hook_opaque);
+
+	int (*reject)(FILE *, const struct fsm_options *opt,
+		void *leaf_opaque, void *hook_opaque);
+
+	void *hook_opaque;
+};
+
 /*
  * Print an FSM to the given file stream. The output is written in the format
  * specified.
@@ -47,7 +78,10 @@ enum fsm_print_lang {
  * Returns 0, or -1 on error and errno will be set. An errno of ENOTSUP means
  * the requested IO API is not implemented for this output language.
  */
-int fsm_print(FILE *f, const struct fsm *fsm, enum fsm_print_lang lang);
+int fsm_print(FILE *f, const struct fsm *fsm,
+	const struct fsm_options *opt,
+	const struct fsm_hooks *hooks,
+	enum fsm_print_lang lang);
 
 #endif
 

include/fsm/vm.h

@@ -5,6 +5,7 @@
 #include <stddef.h>
 
 struct fsm;
+struct fsm_options;
 struct fsm_dfavm;
 
 enum fsm_vm_compile_flags {
@@ -34,7 +35,8 @@ struct fsm_dfavm *
 fsm_vm_compile(const struct fsm *fsm);
 
 struct fsm_dfavm *
-fsm_vm_compile_with_options(const struct fsm *fsm, struct fsm_vm_compile_opts opts);
+fsm_vm_compile_with_options(const struct fsm *fsm,
+	const struct fsm_options *opt, struct fsm_vm_compile_opts opts);
 
 struct fsm_dfavm *
 fsm_vm_read(FILE *f);

include/re/literal.h

@@ -7,7 +7,6 @@
 #ifndef RE_LITERAL_H
 #define RE_LITERAL_H
 
-struct fsm_options;
 struct re_err;
 
 enum re_literal_category {
@@ -20,7 +19,6 @@ enum re_literal_category {
 
 int
 re_is_literal(enum re_dialect dialect, int (*getc)(void *opaque), void *opaque,
-	const struct fsm_options *opt,
 	enum re_flags flags, struct re_err *err,
 	enum re_literal_category *category, char **s, size_t *n);
 

include/re/re.h

@@ -9,7 +9,6 @@
 
 struct fsm;
 struct fsm_alloc;
-struct fsm_options;
 
 enum re_dialect {
 	RE_LIKE,
@@ -135,7 +134,6 @@ struct fsm *
 re_comp(enum re_dialect dialect,
 	re_getchar_fun *f, void *opaque,
 	const struct fsm_alloc *alloc,
-	const struct fsm_options *opt,
 	enum re_flags flags, struct re_err *err);
 
 /*