4 files changed, 67 insertions, 23 deletions

diff --git a/cgit.c b/cgit.cindex 4f31e58..725fd65 100644--- a/cgit.c+++ b/cgit.c@@ -904,6 +904,8 @@ int main(int argc, const char **argv) 	const char *path; 	int err, ttl; +	cgit_init_filters();+ 	prepare_context(&ctx); 	cgit_repolist.length = 0; 	cgit_repolist.count = 0;
diff --git a/cgit.c b/cgit.c
index 4f31e58..725fd65 100644
--- a/cgit.c
+++ b/cgit.c
@@ -904,6 +904,8 @@ int main(int argc, const char **argv)
 	const char *path;
 	int err, ttl;
 
+	cgit_init_filters();
+
 	prepare_context(&ctx);
 	cgit_repolist.length = 0;
 	cgit_repolist.count = 0;
diff --git a/cgit.h b/cgit.hindex 893c38f..519d2af 100644--- a/cgit.h+++ b/cgit.h@@ -61,13 +61,13 @@ struct cgit_filter { 	int (*close)(struct cgit_filter *); 	void (*fprintf)(struct cgit_filter *, FILE *, const char *prefix); 	void (*cleanup)(struct cgit_filter *);+	int argument_count; };  struct cgit_exec_filter { 	struct cgit_filter base; 	char *cmd; 	char **argv;-	int extra_args; 	int old_stdout; 	int pipe_fh[2]; 	int pid;@@ -357,6 +357,7 @@ extern void cgit_fprintf_filter(struct cgit_filter *filter, FILE *f, const char extern void cgit_exec_filter_init(struct cgit_exec_filter *filter, char *cmd, char **argv); extern struct cgit_filter *cgit_new_filter(const char *cmd, filter_type filtertype); extern void cgit_cleanup_filters(void);+extern void cgit_init_filters(void);  extern void cgit_prepare_repo_env(struct cgit_repo * repo); 
diff --git a/cgit.h b/cgit.h
index 893c38f..519d2af 100644
--- a/cgit.h
+++ b/cgit.h
@@ -61,13 +61,13 @@ struct cgit_filter {
 	int (*close)(struct cgit_filter *);
 	void (*fprintf)(struct cgit_filter *, FILE *, const char *prefix);
 	void (*cleanup)(struct cgit_filter *);
+	int argument_count;
 };
 
 struct cgit_exec_filter {
 	struct cgit_filter base;
 	char *cmd;
 	char **argv;
-	int extra_args;
 	int old_stdout;
 	int pipe_fh[2];
 	int pid;
@@ -357,6 +357,7 @@ extern void cgit_fprintf_filter(struct cgit_filter *filter, FILE *f, const char
 extern void cgit_exec_filter_init(struct cgit_exec_filter *filter, char *cmd, char **argv);
 extern struct cgit_filter *cgit_new_filter(const char *cmd, filter_type filtertype);
 extern void cgit_cleanup_filters(void);
+extern void cgit_init_filters(void);
 
 extern void cgit_prepare_repo_env(struct cgit_repo * repo);
 
diff --git a/cgit.mk b/cgit.mkindex 19a76e7..9d6dea8 100644--- a/cgit.mk+++ b/cgit.mk@@ -61,6 +61,8 @@ $(CGIT_VERSION_OBJS): $(CGIT_PREFIX)VERSION $(CGIT_VERSION_OBJS): EXTRA_CPPFLAGS = \ 	-DCGIT_VERSION='"$(CGIT_VERSION)"' +CGIT_LIBS += -ldl+  # Git handles dependencies using ":=" so dependencies in CGIT_OBJ are not # handled by that and we must handle them ourselves.@@ -88,4 +90,4 @@ $(CGIT_OBJS): %.o: %.c GIT-CFLAGS $(CGIT_PREFIX)CGIT-CFLAGS $(missing_dep_dirs) 	$(QUIET_CC)$(CC) -o $*.o -c $(dep_args) $(ALL_CFLAGS) $(EXTRA_CPPFLAGS) $(CGIT_CFLAGS) $<  $(CGIT_PREFIX)cgit: $(CGIT_OBJS) GIT-LDFLAGS $(GITLIBS)-	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS)+	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS) $(CGIT_LIBS)
diff --git a/cgit.mk b/cgit.mk
index 19a76e7..9d6dea8 100644
--- a/cgit.mk
+++ b/cgit.mk
@@ -61,6 +61,8 @@ $(CGIT_VERSION_OBJS): $(CGIT_PREFIX)VERSION
 $(CGIT_VERSION_OBJS): EXTRA_CPPFLAGS = \
 	-DCGIT_VERSION='"$(CGIT_VERSION)"'
 
+CGIT_LIBS += -ldl
+
 
 # Git handles dependencies using ":=" so dependencies in CGIT_OBJ are not
 # handled by that and we must handle them ourselves.
@@ -88,4 +90,4 @@ $(CGIT_OBJS): %.o: %.c GIT-CFLAGS $(CGIT_PREFIX)CGIT-CFLAGS $(missing_dep_dirs)
 	$(QUIET_CC)$(CC) -o $*.o -c $(dep_args) $(ALL_CFLAGS) $(EXTRA_CPPFLAGS) $(CGIT_CFLAGS) $<
 
 $(CGIT_PREFIX)cgit: $(CGIT_OBJS) GIT-LDFLAGS $(GITLIBS)
-	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS)
+	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS) $(CGIT_LIBS)
diff --git a/filter.c b/filter.cindex 30bc74b..f5a5992 100644--- a/filter.c+++ b/filter.c@@ -12,6 +12,11 @@ #include <unistd.h> #include <string.h> #include <stdlib.h>+#include <dlfcn.h>++static ssize_t (*libc_write)(int fd, const void *buf, size_t count);+static ssize_t (*filter_write)(struct cgit_filter *base, const void *buf, size_t count) = NULL;+static struct cgit_filter *current_write_filter = NULL;  static inline void reap_filter(struct cgit_filter *filter) {@@ -32,12 +37,43 @@ void cgit_cleanup_filters(void) 	} } +void cgit_init_filters(void)+{+	libc_write = dlsym(RTLD_NEXT, "write");+	if (!libc_write)+		die("Could not locate libc's write function");+}++ssize_t write(int fd, const void *buf, size_t count)+{+	if (fd != STDOUT_FILENO || !filter_write)+		return libc_write(fd, buf, count);+	return filter_write(current_write_filter, buf, count);+}++static inline void hook_write(struct cgit_filter *filter, ssize_t (*new_write)(struct cgit_filter *base, const void *buf, size_t count))+{+	/* We want to avoid buggy nested patterns. */+	assert(filter_write == NULL);+	assert(current_write_filter == NULL);+	current_write_filter = filter;+	filter_write = new_write;+}++static inline void unhook_write()+{+	assert(filter_write != NULL);+	assert(current_write_filter != NULL);+	filter_write = NULL;+	current_write_filter = NULL;+}+ static int open_exec_filter(struct cgit_filter *base, va_list ap) { 	struct cgit_exec_filter *filter = (struct cgit_exec_filter *) base; 	int i; -	for (i = 0; i < filter->extra_args; i++)+	for (i = 0; i < filter->base.argument_count; i++) 		filter->argv[i+1] = va_arg(ap, char *);  	filter->old_stdout = chk_positive(dup(STDOUT_FILENO),@@ -74,7 +110,7 @@ static int close_exec_filter(struct cgit_filter *base) 	die("Subprocess %s exited abnormally", filter->cmd);  done:-	for (i = 0; i < filter->extra_args; i++)+	for (i = 0; i < filter->base.argument_count; i++) 		filter->argv[i+1] = NULL; 	return 0; @@ -99,7 +135,7 @@ static void cleanup_exec_filter(struct cgit_filter *base) 	} } -static struct cgit_filter *new_exec_filter(const char *cmd, filter_type filtertype)+static struct cgit_filter *new_exec_filter(const char *cmd, int argument_count) { 	struct cgit_exec_filter *f; 	int args_size = 0;@@ -107,20 +143,8 @@ static struct cgit_filter *new_exec_filter(const char *cmd, filter_type filterty 	f = xmalloc(sizeof(*f)); 	/* We leave argv for now and assign it below. */ 	cgit_exec_filter_init(f, xstrdup(cmd), NULL);--	switch (filtertype) {-		case SOURCE:-		case ABOUT:-			f->extra_args = 1;-			break;--		case COMMIT:-		default:-			f->extra_args = 0;-			break;-	}--	args_size = (2 + f->extra_args) * sizeof(char *);+	f->base.argument_count = argument_count;+	args_size = (2 + argument_count) * sizeof(char *); 	f->argv = xmalloc(args_size); 	memset(f->argv, 0, args_size); 	f->argv[0] = f->cmd;@@ -136,6 +160,8 @@ void cgit_exec_filter_init(struct cgit_exec_filter *filter, char *cmd, char **ar 	filter->base.cleanup = cleanup_exec_filter; 	filter->cmd = cmd; 	filter->argv = argv;+	/* The argument count for open_filter is zero by default, unless called from new_filter, above. */+	filter->base.argument_count = 0; }  int cgit_open_filter(struct cgit_filter *filter, ...)@@ -162,7 +188,7 @@ void cgit_fprintf_filter(struct cgit_filter *filter, FILE *f, const char *prefix  static const struct { 	const char *prefix;-	struct cgit_filter *(*ctor)(const char *cmd, filter_type filtertype);+	struct cgit_filter *(*ctor)(const char *cmd, int argument_count); } filter_specs[] = { 	{ "exec", new_exec_filter }, };@@ -172,6 +198,8 @@ struct cgit_filter *cgit_new_filter(const char *cmd, filter_type filtertype) 	char *colon; 	int i; 	size_t len;+	int argument_count;+ 	if (!cmd || !cmd[0]) 		return NULL; @@ -184,16 +212,27 @@ struct cgit_filter *cgit_new_filter(const char *cmd, filter_type filtertype) 	if (len == 1) 		colon = NULL; +	switch (filtertype) {+		case SOURCE:+		case ABOUT:+			argument_count = 1;+			break;++		case COMMIT:+		default:+			argument_count = 0;+			break;+	}+ 	/* If no prefix is given, exec filter is the default. */ 	if (!colon)-		return new_exec_filter(cmd, filtertype);+		return new_exec_filter(cmd, argument_count);  	for (i = 0; i < ARRAY_SIZE(filter_specs); i++) { 		if (len == strlen(filter_specs[i].prefix) && 		    !strncmp(filter_specs[i].prefix, cmd, len))-			return filter_specs[i].ctor(colon + 1, filtertype);+			return filter_specs[i].ctor(colon + 1, argument_count); 	}  	die("Invalid filter type: %.*s", (int) len, cmd); }-
diff --git a/filter.c b/filter.c
index 30bc74b..f5a5992 100644
--- a/filter.c
+++ b/filter.c
@@ -12,6 +12,11 @@
 #include <unistd.h>
 #include <string.h>
 #include <stdlib.h>
+#include <dlfcn.h>
+
+static ssize_t (*libc_write)(int fd, const void *buf, size_t count);
+static ssize_t (*filter_write)(struct cgit_filter *base, const void *buf, size_t count) = NULL;
+static struct cgit_filter *current_write_filter = NULL;
 
 static inline void reap_filter(struct cgit_filter *filter)
 {
@@ -32,12 +37,43 @@ void cgit_cleanup_filters(void)
 	}
 }
 
+void cgit_init_filters(void)
+{
+	libc_write = dlsym(RTLD_NEXT, "write");
+	if (!libc_write)
+		die("Could not locate libc's write function");
+}
+
+ssize_t write(int fd, const void *buf, size_t count)
+{
+	if (fd != STDOUT_FILENO || !filter_write)
+		return libc_write(fd, buf, count);
+	return filter_write(current_write_filter, buf, count);
+}
+
+static inline void hook_write(struct cgit_filter *filter, ssize_t (*new_write)(struct cgit_filter *base, const void *buf, size_t count))
+{
+	/* We want to avoid buggy nested patterns. */
+	assert(filter_write == NULL);
+	assert(current_write_filter == NULL);
+	current_write_filter = filter;
+	filter_write = new_write;
+}
+
+static inline void unhook_write()
+{
+	assert(filter_write != NULL);
+	assert(current_write_filter != NULL);
+	filter_write = NULL;
+	current_write_filter = NULL;
+}
+
 static int open_exec_filter(struct cgit_filter *base, va_list ap)
 {
 	struct cgit_exec_filter *filter = (struct cgit_exec_filter *) base;
 	int i;
 
-	for (i = 0; i < filter->extra_args; i++)
+	for (i = 0; i < filter->base.argument_count; i++)
 		filter->argv[i+1] = va_arg(ap, char *);
 
 	filter->old_stdout = chk_positive(dup(STDOUT_FILENO),
@@ -74,7 +110,7 @@ static int close_exec_filter(struct cgit_filter *base)
 	die("Subprocess %s exited abnormally", filter->cmd);
 
 done:
-	for (i = 0; i < filter->extra_args; i++)
+	for (i = 0; i < filter->base.argument_count; i++)
 		filter->argv[i+1] = NULL;
 	return 0;
 
@@ -99,7 +135,7 @@ static void cleanup_exec_filter(struct cgit_filter *base)
 	}
 }
 
-static struct cgit_filter *new_exec_filter(const char *cmd, filter_type filtertype)
+static struct cgit_filter *new_exec_filter(const char *cmd, int argument_count)
 {
 	struct cgit_exec_filter *f;
 	int args_size = 0;
@@ -107,20 +143,8 @@ static struct cgit_filter *new_exec_filter(const char *cmd, filter_type filterty
 	f = xmalloc(sizeof(*f));
 	/* We leave argv for now and assign it below. */
 	cgit_exec_filter_init(f, xstrdup(cmd), NULL);
-
-	switch (filtertype) {
-		case SOURCE:
-		case ABOUT:
-			f->extra_args = 1;
-			break;
-
-		case COMMIT:
-		default:
-			f->extra_args = 0;
-			break;
-	}
-
-	args_size = (2 + f->extra_args) * sizeof(char *);
+	f->base.argument_count = argument_count;
+	args_size = (2 + argument_count) * sizeof(char *);
 	f->argv = xmalloc(args_size);
 	memset(f->argv, 0, args_size);
 	f->argv[0] = f->cmd;
@@ -136,6 +160,8 @@ void cgit_exec_filter_init(struct cgit_exec_filter *filter, char *cmd, char **ar
 	filter->base.cleanup = cleanup_exec_filter;
 	filter->cmd = cmd;
 	filter->argv = argv;
+	/* The argument count for open_filter is zero by default, unless called from new_filter, above. */
+	filter->base.argument_count = 0;
 }
 
 int cgit_open_filter(struct cgit_filter *filter, ...)
@@ -162,7 +188,7 @@ void cgit_fprintf_filter(struct cgit_filter *filter, FILE *f, const char *prefix
 
 static const struct {
 	const char *prefix;
-	struct cgit_filter *(*ctor)(const char *cmd, filter_type filtertype);
+	struct cgit_filter *(*ctor)(const char *cmd, int argument_count);
 } filter_specs[] = {
 	{ "exec", new_exec_filter },
 };
@@ -172,6 +198,8 @@ struct cgit_filter *cgit_new_filter(const char *cmd, filter_type filtertype)
 	char *colon;
 	int i;
 	size_t len;
+	int argument_count;
+
 	if (!cmd || !cmd[0])
 		return NULL;
 
@@ -184,16 +212,27 @@ struct cgit_filter *cgit_new_filter(const char *cmd, filter_type filtertype)
 	if (len == 1)
 		colon = NULL;
 
+	switch (filtertype) {
+		case SOURCE:
+		case ABOUT:
+			argument_count = 1;
+			break;
+
+		case COMMIT:
+		default:
+			argument_count = 0;
+			break;
+	}
+
 	/* If no prefix is given, exec filter is the default. */
 	if (!colon)
-		return new_exec_filter(cmd, filtertype);
+		return new_exec_filter(cmd, argument_count);
 
 	for (i = 0; i < ARRAY_SIZE(filter_specs); i++) {
 		if (len == strlen(filter_specs[i].prefix) &&
 		    !strncmp(filter_specs[i].prefix, cmd, len))
-			return filter_specs[i].ctor(colon + 1, filtertype);
+			return filter_specs[i].ctor(colon + 1, argument_count);
 	}
 
 	die("Invalid filter type: %.*s", (int) len, cmd);
 }
-