Implement -fprint and -fprint0.

4 files changed, 123 insertions, 9 deletions

diff --git a/bfs.h b/bfs.h
index f6f120d..a6c7264 100644
--- a/bfs.h
+++ b/bfs.h
@@ -15,6 +15,7 @@
 #include "color.h"
 #include <stdbool.h>
 #include <stddef.h>
+#include <stdio.h>
 #include <sys/types.h>
 #include <time.h>
 
@@ -91,6 +92,9 @@ struct cmdline {
 
 	/** The command line expression. */
 	struct expr *expr;
+
+	/** The number of open files used by the expression tree. */
+	int nopen_files;
 };
 
 /**
@@ -192,6 +196,9 @@ struct expr {
 	/** Optional inode number for a target file. */
 	ino_t ino;
 
+	/** File to output to. */
+	FILE *file;
+
 	/** Optional -exec flags. */
 	enum execflags execflags;
 
@@ -247,6 +254,7 @@ bool eval_delete(const struct expr *expr, struct eval_state *state);
 bool eval_exec(const struct expr *expr, struct eval_state *state);
 bool eval_nohidden(const struct expr *expr, struct eval_state *state);
 bool eval_print(const struct expr *expr, struct eval_state *state);
+bool eval_fprint(const struct expr *expr, struct eval_state *state);
 bool eval_print0(const struct expr *expr, struct eval_state *state);
 bool eval_prune(const struct expr *expr, struct eval_state *state);
 bool eval_quit(const struct expr *expr, struct eval_state *state);
diff --git a/eval.c b/eval.c
index 828a33f..c3e29d2 100644
--- a/eval.c
+++ b/eval.c
@@ -626,11 +626,21 @@ bool eval_print(const struct expr *expr, struct eval_state *state) {
 }
 
 /**
- * -print0 action.
+ * -fprint action.
+ */
+bool eval_fprint(const struct expr *expr, struct eval_state *state) {
+	const char *path = state->ftwbuf->path;
+	fputs(path, expr->file);
+	fputc('\n', expr->file);
+	return true;
+}
+
+/**
+ * -f?print0 action.
  */
 bool eval_print0(const struct expr *expr, struct eval_state *state) {
 	const char *path = state->ftwbuf->path;
-	fwrite(path, 1, strlen(path) + 1, stdout);
+	fwrite(path, 1, strlen(path) + 1, expr->file);
 	return true;
 }
 
@@ -857,7 +867,7 @@ static enum bftw_action cmdline_callback(struct BFTW *ftwbuf, void *ptr) {
 /**
  * Infer the number of open file descriptors we're allowed to have.
  */
-static int infer_fdlimit() {
+static int infer_fdlimit(const struct cmdline *cmdline) {
 	int ret = 4096;
 
 	struct rlimit rl;
@@ -867,8 +877,8 @@ static int infer_fdlimit() {
 		}
 	}
 
-	// std{in,out,err}
-	int nopen = 3;
+	// 3 for std{in,out,err}
+	int nopen = 3 + cmdline->nopen_files;
 
 	// Check /dev/fd for the current number of open fds, if possible (we may
 	// have inherited more than just the standard ones)
@@ -914,7 +924,7 @@ int eval_cmdline(const struct cmdline *cmdline) {
 		return 0;
 	}
 
-	int nopenfd = infer_fdlimit();
+	int nopenfd = infer_fdlimit(cmdline);
 
 	struct callback_args args = {
 		.cmdline = cmdline,
diff --git a/parse.c b/parse.c
index cccdacf..4101c36 100644
--- a/parse.c
+++ b/parse.c
@@ -62,6 +62,12 @@ static struct expr expr_false = {
  */
 static void free_expr(struct expr *expr) {
 	if (expr && expr != &expr_true && expr != &expr_false) {
+		if (expr->file && expr->file != stdout && expr->file != stderr) {
+			if (fclose(expr->file) != 0) {
+				perror("fclose()");
+			}
+		}
+
 		free_expr(expr->lhs);
 		free_expr(expr->rhs);
 		free(expr);
@@ -80,6 +86,7 @@ static struct expr *new_expr(eval_fn *eval, bool pure, size_t argc, char **argv)
 		expr->pure = pure;
 		expr->argc = argc;
 		expr->argv = argv;
+		expr->file = NULL;
 	}
 	return expr;
 }
@@ -259,7 +266,7 @@ static int stat_arg(const struct parser_state *state, struct expr *expr, struct
 	int ret = fstatat(AT_FDCWD, expr->sdata, sb, flags);
 	if (ret != 0) {
 		pretty_error(cmdline->stderr_colors,
-		             "'%s': %s\n", expr->sdata, strerror(errno));
+		             "error: '%s': %s\n", expr->sdata, strerror(errno));
 		free_expr(expr);
 	}
 	return ret;
@@ -508,6 +515,25 @@ static struct expr *parse_nullary_action(struct parser_state *state, eval_fn *ev
 }
 
 /**
+ * Parse an action that takes one argument.
+ */
+static struct expr *parse_unary_action(struct parser_state *state, eval_fn *eval) {
+	const char *arg = state->argv[0];
+	const char *value = state->argv[1];
+	if (!value) {
+		pretty_error(state->cmdline->stderr_colors,
+		             "error: %s needs a value.\n", arg);
+		return NULL;
+	}
+
+	struct expr *expr = parse_action(state, eval, 2);
+	if (expr) {
+		expr->sdata = value;
+	}
+	return expr;
+}
+
+/**
  * Parse a test expression with integer data and a comparison flag.
  */
 static struct expr *parse_test_icmp(struct parser_state *state, eval_fn *eval) {
@@ -703,6 +729,59 @@ static struct expr *parse_exec(struct parser_state *state, enum execflags flags)
 }
 
 /**
+ * Open a file for an expression.
+ */
+static int expr_open(struct parser_state *state, struct expr *expr, const char *path) {
+	expr->file = fopen(path, "wb");
+	if (!expr->file) {
+		pretty_error(state->cmdline->stderr_colors,
+		             "error: '%s': %s\n", path, strerror(errno));
+		free_expr(expr);
+		return -1;
+	}
+
+	++state->cmdline->nopen_files;
+	return 0;
+}
+
+/**
+ * Parse -fprint FILE.
+ */
+static struct expr *parse_fprint(struct parser_state *state) {
+	struct expr *expr = parse_unary_action(state, eval_fprint);
+	if (expr) {
+		if (expr_open(state, expr, expr->sdata) != 0) {
+			return NULL;
+		}
+	}
+	return expr;
+}
+
+/**
+ * Parse -fprint0 FILE.
+ */
+static struct expr *parse_fprint0(struct parser_state *state) {
+	struct expr *expr = parse_unary_action(state, eval_print0);
+	if (expr) {
+		if (expr_open(state, expr, expr->sdata) != 0) {
+			return NULL;
+		}
+	}
+	return expr;
+}
+
+/**
+ * Parse -print0.
+ */
+static struct expr *parse_print0(struct parser_state *state) {
+	struct expr *expr = parse_nullary_action(state, eval_print0);
+	if (expr) {
+		expr->file = stdout;
+	}
+	return expr;
+}
+
+/**
  * Parse -group.
  */
 static struct expr *parse_group(struct parser_state *state) {
@@ -1176,6 +1255,10 @@ static struct expr *parse_literal(struct parser_state *state) {
 		} else if (strcmp(arg, "-follow") == 0) {
 			cmdline->flags |= BFTW_FOLLOW | BFTW_DETECT_CYCLES;
 			return parse_nullary_positional_option(state);
+		} else if (strcmp(arg, "-fprint") == 0) {
+			return parse_fprint(state);
+		} else if (strcmp(arg, "-fprint0") == 0) {
+			return parse_fprint0(state);
 		}
 		break;
 
@@ -1265,7 +1348,7 @@ static struct expr *parse_literal(struct parser_state *state) {
 		} else if (strcmp(arg, "-print") == 0) {
 			return parse_nullary_action(state, eval_print);
 		} else if (strcmp(arg, "-print0") == 0) {
-			return parse_nullary_action(state, eval_print0);
+			return parse_print0(state);
 		} else if (strcmp(arg, "-prune") == 0) {
 			return parse_nullary_action(state, eval_prune);
 		}
@@ -1756,6 +1839,7 @@ struct cmdline *parse_cmdline(int argc, char *argv[]) {
 	cmdline->optlevel = 2;
 	cmdline->debug = 0;
 	cmdline->expr = &expr_true;
+	cmdline->nopen_files = 0;
 
 	cmdline->colors = parse_colors(getenv("LS_COLORS"));
 	cmdline->stdout_colors = isatty(STDOUT_FILENO) ? cmdline->colors : NULL;
diff --git a/tests.sh b/tests.sh
index d4ac7fc..ead81f6 100755
--- a/tests.sh
+++ b/tests.sh
@@ -62,8 +62,11 @@ function make_weirdnames() {
 weirdnames="$(mktemp -d "${TMPDIR:-/tmp}"/bfs.weirdnames.XXXXXXXXXX)"
 make_weirdnames "$weirdnames"
 
+out="$(mktemp -d "${TMPDIR:-/tmp}"/bfs.out.XXXXXXXXXX)"
+
 # Clean up temporary directories on exit
 function cleanup() {
+    rm -rf "$out"
     rm -rf "$weirdnames"
     rm -rf "$links"
     rm -rf "$perms"
@@ -340,7 +343,16 @@ function test_0061() {
     find_diff '-' '(-' '!-' ',' ')' './(' './!' \( \! -print , -print \)
 }
 
-for i in {1..61}; do
+function test_0062() {
+    find "$basic" -fprint "$out/out.find"
+    "$BFS" "$basic" -fprint "$out/out.bfs"
+
+    sort -o "$out/out.find" "$out/out.find"
+    sort -o "$out/out.bfs" "$out/out.bfs"
+    diff -u "$out/out.find" "$out/out.bfs"
+}
+
+for i in {1..62}; do
     test="test_$(printf '%04d' $i)"
     ("$test" "$dir")
     status=$?