Add -[acm]{min,time} support.

3 files changed, 242 insertions, 30 deletions

diff --git a/bfs.h b/bfs.h
index 441993b..e4dffdd 100644
--- a/bfs.h
+++ b/bfs.h
@@ -15,6 +15,7 @@
 #include "color.h"
 #include <stdbool.h>
 #include <stddef.h>
+#include <time.h>
 
 /**
  * The parsed command line.
@@ -64,8 +65,23 @@ struct cmdline {
 
 	/** The command line expression. */
 	expression *expr;
+
+	/** The current time. */
+	struct timespec now;
 };
 
+/**
+ * Possible types of numeric comparison.
+ */
+typedef enum {
+	/** Exactly n. */
+	CMP_EXACT,
+	/** Less than n. */
+	CMP_LESS,
+	/** Greater than n. */
+	CMP_GREATER,
+} cmpflag;
+
 struct expression {
 	/** The left hand side of the expression. */
 	expression *lhs;
@@ -73,6 +89,8 @@ struct expression {
 	expression *rhs;
 	/** The function that evaluates this expression. */
 	eval_fn *eval;
+	/** The comparison flag. */
+	cmpflag cmp;
 	/** Optional integer data for this expression. */
 	int idata;
 	/** Optional string data for this expression. */
@@ -95,20 +113,31 @@ int eval_cmdline(cmdline *cl);
 void free_cmdline(cmdline *cl);
 
 // Predicate evaluation functions
+bool eval_true(const expression *expr, eval_state *state);
+bool eval_false(const expression *expr, eval_state *state);
+
 bool eval_access(const expression *expr, eval_state *state);
-bool eval_delete(const expression *expr, eval_state *state);
+
+bool eval_amin(const expression *expr, eval_state *state);
+bool eval_atime(const expression *expr, eval_state *state);
+bool eval_cmin(const expression *expr, eval_state *state);
+bool eval_ctime(const expression *expr, eval_state *state);
+bool eval_mmin(const expression *expr, eval_state *state);
+bool eval_mtime(const expression *expr, eval_state *state);
+
 bool eval_empty(const expression *expr, eval_state *state);
-bool eval_false(const expression *expr, eval_state *state);
 bool eval_hidden(const expression *expr, eval_state *state);
+bool eval_type(const expression *expr, eval_state *state);
+
 bool eval_name(const expression *expr, eval_state *state);
-bool eval_nohidden(const expression *expr, eval_state *state);
 bool eval_path(const expression *expr, eval_state *state);
+
+bool eval_delete(const expression *expr, eval_state *state);
+bool eval_nohidden(const expression *expr, eval_state *state);
 bool eval_print(const expression *expr, eval_state *state);
 bool eval_print0(const expression *expr, eval_state *state);
 bool eval_prune(const expression *expr, eval_state *state);
 bool eval_quit(const expression *expr, eval_state *state);
-bool eval_true(const expression *expr, eval_state *state);
-bool eval_type(const expression *expr, eval_state *state);
 
 // Operator evaluation functions
 bool eval_not(const expression *expr, eval_state *state);
diff --git a/eval.c b/eval.c
index 417bfc3..243546e 100644
--- a/eval.c
+++ b/eval.c
@@ -8,6 +8,7 @@
 #include <string.h>
 #include <sys/resource.h>
 #include <sys/stat.h>
+#include <time.h>
 #include <unistd.h>
 
 struct eval_state {
@@ -24,17 +25,57 @@ struct eval_state {
 /**
  * Perform a stat() call if necessary.
  */
-static void fill_statbuf(eval_state *state) {
+static const struct stat *fill_statbuf(eval_state *state) {
 	struct BFTW *ftwbuf = state->ftwbuf;
-	if (ftwbuf->statbuf) {
-		return;
+	if (!ftwbuf->statbuf) {
+		if (fstatat(ftwbuf->at_fd, ftwbuf->at_path, &state->statbuf, AT_SYMLINK_NOFOLLOW) == 0) {
+			ftwbuf->statbuf = &state->statbuf;
+		} else {
+			perror("fstatat()");
+		}
 	}
+	return ftwbuf->statbuf;
+}
 
-	if (fstatat(ftwbuf->at_fd, ftwbuf->at_path, &state->statbuf, AT_SYMLINK_NOFOLLOW) == 0) {
-		ftwbuf->statbuf = &state->statbuf;
-	} else {
-		perror("fstatat()");
+/**
+ * Get the difference (in seconds) between two struct timespecs.
+ */
+static time_t timespec_diff(const struct timespec *lhs, const struct timespec *rhs) {
+	time_t ret = lhs->tv_sec - rhs->tv_sec;
+	if (lhs->tv_nsec < rhs->tv_nsec) {
+		--ret;
+	}
+	return ret;
+}
+
+/**
+ * Convert a second count to minutes.
+ */
+static time_t to_minutes(time_t seconds) {
+	return seconds/60;
+}
+
+/**
+ * Convert a second count to days.
+ */
+static time_t to_days(time_t seconds) {
+	return seconds/60/60/24;
+}
+
+/**
+ * Perform a comparison.
+ */
+static bool do_cmp(const expression *expr, int n) {
+	switch (expr->cmp) {
+	case CMP_EXACT:
+		return n == expr->idata;
+	case CMP_LESS:
+		return n < expr->idata;
+	case CMP_GREATER:
+		return n > expr->idata;
 	}
+
+	return false;
 }
 
 /**
@@ -52,7 +93,7 @@ bool eval_false(const expression *expr, eval_state *state) {
 }
 
 /**
- * -executable, -readable, -writable action.
+ * -executable, -readable, -writable tests.
  */
 bool eval_access(const expression *expr, eval_state *state) {
 	struct BFTW *ftwbuf = state->ftwbuf;
@@ -60,6 +101,84 @@ bool eval_access(const expression *expr, eval_state *state) {
 }
 
 /**
+ * -amin test.
+ */
+bool eval_amin(const expression *expr, eval_state *state) {
+	const struct stat *statbuf = fill_statbuf(state);
+	if (!statbuf) {
+		return false;
+	}
+
+	time_t diff = timespec_diff(&state->cl->now, &statbuf->st_atim);
+	return do_cmp(expr, to_minutes(diff));
+}
+
+/**
+ * -atime test.
+ */
+bool eval_atime(const expression *expr, eval_state *state) {
+	const struct stat *statbuf = fill_statbuf(state);
+	if (!statbuf) {
+		return false;
+	}
+
+	time_t diff = timespec_diff(&state->cl->now, &statbuf->st_atim);
+	return do_cmp(expr, to_days(diff));
+}
+
+/**
+ * -cmin test.
+ */
+bool eval_cmin(const expression *expr, eval_state *state) {
+	const struct stat *statbuf = fill_statbuf(state);
+	if (!statbuf) {
+		return false;
+	}
+
+	time_t diff = timespec_diff(&state->cl->now, &statbuf->st_ctim);
+	return do_cmp(expr, to_minutes(diff));
+}
+
+/**
+ * -ctime test.
+ */
+bool eval_ctime(const expression *expr, eval_state *state) {
+	const struct stat *statbuf = fill_statbuf(state);
+	if (!statbuf) {
+		return false;
+	}
+
+	time_t diff = timespec_diff(&state->cl->now, &statbuf->st_ctim);
+	return do_cmp(expr, to_days(diff));
+}
+
+/**
+ * -mmin test.
+ */
+bool eval_mmin(const expression *expr, eval_state *state) {
+	const struct stat *statbuf = fill_statbuf(state);
+	if (!statbuf) {
+		return false;
+	}
+
+	time_t diff = timespec_diff(&state->cl->now, &statbuf->st_mtim);
+	return do_cmp(expr, to_minutes(diff));
+}
+
+/**
+ * -mtime test.
+ */
+bool eval_mtime(const expression *expr, eval_state *state) {
+	const struct stat *statbuf = fill_statbuf(state);
+	if (!statbuf) {
+		return false;
+	}
+
+	time_t diff = timespec_diff(&state->cl->now, &statbuf->st_mtim);
+	return do_cmp(expr, to_days(diff));
+}
+
+/**
  * -delete action.
  */
 bool eval_delete(const expression *expr, eval_state *state) {
@@ -111,9 +230,9 @@ bool eval_empty(const expression *expr, eval_state *state) {
 
 		closedir(dir);
 	} else {
-		fill_statbuf(state);
-		if (ftwbuf->statbuf) {
-			ret = ftwbuf->statbuf->st_size == 0;
+		const struct stat *statbuf = fill_statbuf(state);
+		if (statbuf) {
+			ret = statbuf->st_size == 0;
 		}
 	}
 
diff --git a/parse.c b/parse.c
index 5425afa..6983f16 100644
--- a/parse.c
+++ b/parse.c
@@ -18,6 +18,7 @@ static expression *new_expression(eval_fn *eval) {
 	expr->lhs = NULL;
 	expr->rhs = NULL;
 	expr->eval = eval;
+	expr->cmp = CMP_EXACT;
 	expr->idata = 0;
 	expr->sdata = NULL;
 	return expr;
@@ -164,6 +165,50 @@ static const char *skip_paths(parser_state *state) {
 }
 
 /**
+ * Parse an integer.
+ */
+static bool parse_int(const char *str, int *value) {
+	char *endptr;
+	long result = strtol(str, &endptr, 10);
+
+	if (*str == '\0' || *endptr != '\0') {
+		goto bad;
+	}
+
+	if (result < INT_MIN || result > INT_MAX) {
+		goto bad;
+	}
+
+	*value = result;
+	return true;
+
+bad:
+	fprintf(stderr, "'%s' is not a valid integer.\n", str);
+	return false;
+}
+
+/**
+ * Parse an integer and a comparison flag.
+ */
+static bool parse_icmp(const char *str, expression *expr) {
+	switch (str[0]) {
+	case '-':
+		expr->cmp = CMP_LESS;
+		++str;
+		break;
+	case '+':
+		expr->cmp = CMP_GREATER;
+		++str;
+		break;
+	default:
+		expr->cmp = CMP_EXACT;
+		break;
+	}
+
+	return parse_int(str, &expr->idata);
+}
+
+/**
  * Create a new option expression.
  */
 static expression *new_option(parser_state *state, const char *option) {
@@ -228,22 +273,25 @@ static expression *new_action(parser_state *state, eval_fn *eval) {
 }
 
 /**
- * Parse an integer.
+ * Parse a test expression with integer data and a comparison flag.
  */
-static bool parse_int(const char *str, int *value) {
-	char *endptr;
-	long result = strtol(str, &endptr, 10);
-
-	if (*str == '\0' || *endptr != '\0') {
-		return false;
+static expression *parse_test_icmp(parser_state *state, const char *test, eval_fn *eval) {
+	const char *arg = state->argv[state->i];
+	if (!arg) {
+		fprintf(stderr, "%s needs a value.\n", test);
+		return NULL;
 	}
 
-	if (result < INT_MIN || result > INT_MAX) {
-		return false;
-	}
+	++state->i;
 
-	*value = result;
-	return true;
+	expression *expr = new_test(state, eval);
+	if (expr) {
+		if (!parse_icmp(arg, expr)) {
+			free_expression(expr);
+			expr = NULL;
+		}
+	}
+	return expr;
 }
 
 /**
@@ -274,7 +322,6 @@ static expression *parse_depth(parser_state *state, const char *option, int *dep
 	++state->i;
 
 	if (!parse_int(arg, depth)) {
-		fprintf(stderr, "%s is not a valid integer.\n", arg);
 		return NULL;
 	}
 
@@ -336,7 +383,15 @@ static expression *parse_literal(parser_state *state) {
 	// Paths are already skipped at this point
 	const char *arg = state->argv[state->i++];
 
-	if (strcmp(arg, "-color") == 0) {
+	if (strcmp(arg, "-amin") == 0) {
+		return parse_test_icmp(state, arg, eval_amin);
+	} else if (strcmp(arg, "-atime") == 0) {
+		return parse_test_icmp(state, arg, eval_atime);
+	} else if (strcmp(arg, "-cmin") == 0) {
+		return parse_test_icmp(state, arg, eval_cmin);
+	} else if (strcmp(arg, "-ctime") == 0) {
+		return parse_test_icmp(state, arg, eval_ctime);
+	} else if (strcmp(arg, "-color") == 0) {
 		state->cl->color = true;
 		return new_option(state, arg);
 	} else if (strcmp(arg, "-nocolor") == 0) {
@@ -362,6 +417,10 @@ static expression *parse_literal(parser_state *state) {
 		return parse_depth(state, arg, &state->cl->mindepth);
 	} else if (strcmp(arg, "-maxdepth") == 0) {
 		return parse_depth(state, arg, &state->cl->maxdepth);
+	} else if (strcmp(arg, "-mmin") == 0) {
+		return parse_test_icmp(state, arg, eval_mmin);
+	} else if (strcmp(arg, "-mtime") == 0) {
+		return parse_test_icmp(state, arg, eval_mtime);
 	} else if (strcmp(arg, "-name") == 0) {
 		return parse_test_sdata(state, arg, eval_name);
 	} else if (strcmp(arg, "-path") == 0 || strcmp(arg, "-wholename") == 0) {
@@ -613,6 +672,11 @@ cmdline *parse_cmdline(int argc, char *argv[]) {
 	cl->flags = BFTW_RECOVER;
 	cl->expr = &expr_true;
 
+	if (clock_gettime(CLOCK_REALTIME, &cl->now) != 0) {
+		perror("clock_gettime()");
+		goto fail;
+	}
+
 	parser_state state = {
 		.cl = cl,
 		.argv = argv,