Add ability to select multiple screens

Signed-off-by: Mattias Andrée <m@maandree.se>

4 files changed, 97 insertions, 48 deletions

diff --git a/README b/README
index 976764b..5ff673f 100644
--- a/README
+++ b/README
@@ -607,17 +607,20 @@ EXTENDED DESCRIPTION
 	available on Unix-like systems) and "corelocation" (available on
 	Mac OS X).
 
-	Options for the location provider "randr" (preferred method for X) are:
+	Options for the adjustment method "randr" (preferred method for X) are:
 
 	display = name
 		X display to apply adjustments to. Default is determined
 		by the environment variable DISPLAY.
 
 	screen = ordinal
-		X screen to apply adjustments to. All will be used if not
-		specified.
+		Comma-separated (,) list of X screens to apply adjustments to.
+		All available X screens are used if the list is empty or if the
+		setting is omitted.
 
-	crtc = number list or all
+		"all" may be specified as a synonym for an empty list.
+
+	crtc = number list or "all"
 		Comma-separated (,) list of CRTC numbers for monitors to
 		apply adjustments to. All available CRTCs are used if the
 		list is empty or if the setting is omitted.
@@ -632,7 +635,7 @@ EXTENDED DESCRIPTION
 
 		The index of the first CRTC is 0.
 
-	edid = name list or list
+	edid = name list or "list"
 		Comma-separated (,) list of EDIDs of monitors to apply
 		adjustments to.
 
@@ -642,23 +645,30 @@ EXTENDED DESCRIPTION
 		This list must not be empty; to select all monitors,
 		instead specify crtc=all.
 
-	Options for the location provider "vidmode" (fallback method for X) are:
+	Options for the adjustment method "vidmode" (fallback method for X) are:
 
 	display = name
 		X display to apply adjustments to. Default is determined
 		by the environment variable DISPLAY.
 
-	screen = ordinal
-		X screen to apply adjustments to. All will be used if not
-		specified.
+	screen = ordinal list or "all"
+		Comma-separated (,) list of X screens to apply adjustments to.
+		All available X screens are used if the list is empty or if the
+		setting is omitted.
 
-	Options for the location provider "drm" (method for Linux without
+		"all" may be specified as a synonym for an empty list.
+
+	Options for the adjustment method "drm" (method for Linux without
 	display server) are:
 
-	card = ordinal
-		Index of graphics card to apply adjustments to.
+	card = ordinal list or "all"
+		Comma-separated (,) list of indices of graphics card screens to
+		apply adjustments to. All available graphics cards are used if
+		the list is empty or if the setting is omitted.
+
+		"all" may be specified as a synonym for an empty list.
 
-	crtc = number list or all
+	crtc = number list or "all"
 		Comma-separated (,) list of CRTC numbers for monitors to
 		apply adjustments to. All available CRTCs are used if the
 		list is empty or if the setting is omitted.
@@ -673,7 +683,7 @@ EXTENDED DESCRIPTION
 
 		The index of the first CRTC is 0.
 
-	edid = name list or list
+	edid = name list or "list"
 		Comma-separated (,) list of EDIDs of monitors to apply
 		adjustments to.
 
diff --git a/TODO b/TODO
index 1b0748c..f813cc0 100644
--- a/TODO
+++ b/TODO
@@ -143,7 +143,6 @@ When disabled, redshift should be periodically set the gamma ramps
 Add signals for setting location
 Add signals for responding with sigqueue the state of redshift
 
-Add support for selecting multiple screens
 Document option delimiter for -l and -m
 The method option "display" requires support for ":", use ";" delimit after "display"
 	":" cannot be changed to ";" for all options are this would break backwards
diff --git a/redshift.1 b/redshift.1
index bd9b1bc..944da66 100644
--- a/redshift.1
+++ b/redshift.1
@@ -947,7 +947,7 @@ There are no options for the location providers
 .B corelocation
 (available on Mac OS X).
 .PP
-Options for the location provider
+Options for the adjustment method
 .B randr
 (preferred method for X) are:
 .TP
@@ -956,9 +956,15 @@ X display to apply adjustments to. Default is determined
 by the environment variable
 .IR DISPLAY .
 .TP
-.BI screen\fR\ =\  ordinal
-X screen to apply adjustments to. All will be used if not
-specified.
+.BI screen\fR\ =\  "ordinal list or " all
+Comma-separated
+.RB ( , )
+list of X screens to apply adjustments to.
+All available X screens are used if the list is empty or
+if the setting is omitted.
+
+.B all
+may be specified as a synonym for an empty list.
 .TP
 .BI crtc\fR\ =\  "number list or " all
 Comma-separated
@@ -995,7 +1001,7 @@ This list must not be empty; to select all monitors,
 instead specify
 .BR crtc=all .
 .PP
-Options for the location provider
+Options for the adjustment method
 .B vidmode
 (fallback method for X) are:
 .TP
@@ -1003,17 +1009,30 @@ Options for the location provider
 X display to apply adjustments to. Default is determined
 by the environment variable
 .IR DISPLAY .
-.TP
-.BI screen\fR\ =\  ordinal
-X screen to apply adjustments to. All will be used if not
-specified.
+.BI screen\fR\ =\  "ordinal list or " all
+Comma-separated
+.RB ( , )
+list of X screens to apply adjustments to.
+All available X screens are used if the list is empty or
+if the setting is omitted.
+
+.B all
+may be specified as a synonym for an empty list.
 .PP
-Options for the location provider
+Options for the adjustment method
 .B drm
 (method for Linux without display server) are:
 .TP
-.BI card\fR\ =\  ordinal
-Index of graphics card to apply adjustments to.
+.BI card\fR\ =\  "ordinal list or " all
+Comma-separated
+.RB ( , )
+list of indices of graphics card screens to apply
+adjustments to. All available graphics cards
+are used if the list is empty or
+if the setting is omitted.
+
+.B all
+may be specified as a synonym for an empty list.
 .TP
 .BI crtc\fR\ =\  "number list or " all
 Comma-separated
diff --git a/src/backend-direct.c b/src/backend-direct.c
index de58548..37c82c6 100644
--- a/src/backend-direct.c
+++ b/src/backend-direct.c
@@ -140,7 +140,7 @@ struct gamma_state {
 	/**
 	 * Whether a parition has been selected
 	 */
-	unsigned partition_selected : 1;
+	unsigned partitions_selected : 1;
 
 	/**
 	 * Whether CRTCs have been selected
@@ -158,11 +158,6 @@ struct gamma_state {
 	int method;
 
 	/**
-	 * Selected parition (if `partition_selected`)
-	 */
-	size_t selected_partition;
-
-	/**
 	 * Number of selected CRTCs
 	 */
 	size_t ncrtcs;
@@ -178,6 +173,11 @@ struct gamma_state {
 	size_t npartitions;
 
 	/**
+	 * Selected paritions (if `partitions_selected`)
+	 */
+	size_t *selected_partitions;
+
+	/**
 	 * Selected CRTC numbers
 	 * 
 	 * Deallocated by when no longer needed
@@ -274,7 +274,7 @@ direct_print_help(FILE *f, int method)
 		fprintf(f, "  card=%s     %s\n", _("N     "), _("Graphics card to apply adjustments to"));
 	} else if (caps.multiple_partitions) {
 		/* TRANSLATORS: "N" represents "ordinal"; right-pad with spaces to preserve display width */
-		fprintf(f, "  screen=%s   %s\n", _("N     "), _("X screen to apply adjustments to"));
+		fprintf(f, "  screen=%s   %s\n", _("N     "), _("List of comma-separated X screens to apply adjustments to"));
 	}
 
 	if (caps.multiple_crtcs) {
@@ -327,21 +327,38 @@ direct_set_site(struct gamma_state *state, const char *key, const char *value)
 int
 direct_set_partitions(struct gamma_state *state, const char *key, const char *value)
 {
-	const char *end;
+	const char *end, *p;
 	uintmax_t num;
+	size_t count;
 
 	/* Check previously unspecified */
-	if (state->partition_selected)
+	if (state->partitions_selected)
 		weprintf(_("`%s' option specified multiple times, using last selection."), key);
-	state->partition_selected = 1;
+	state->partitions_selected = 1;
 
-	/* Parse number */
+	/* Check if all are selected */
+	state->npartitions = 0;
+	free(state->selected_partitions);
+	state->selected_partitions = NULL;
+	if (!*value || !strcasecmp(value, "all"))
+		return 0;
+
+	/* Get number count */
+	for (p = value, count = 1; *p; p++)
+		if (*p == ',')
+			count++;
+	state->selected_partitions = ecalloc(count, sizeof(*state->selected_partitions));
+
+	/* Parse numbers */
 	errno = 0;
-	num = strtoumax(value, (void *)&end, 10);
-	state->selected_partition = (size_t)num;
-	if (num > (uintmax_t)SIZE_MAX || *end || !isdigit(*value) || errno) {
-		weprintf(_("Invalid value of `%s' option: `%s'."), key, value);
-		return -1;
+	for (p = value; *p; p = end) {
+		num = strtoumax(p, (void *)&end, 10);
+		state->selected_partitions[state->npartitions++] = (size_t)num;
+		if (num > (uintmax_t)SIZE_MAX || (*end && *end != ',') || !isdigit(*p) || errno) {
+			weprintf(_("Invalid value of `%s' option: `%s'."), key, value);
+			return -1;
+		}
+		end = &end[*end == ','];
 	}
 
 	return 0;
@@ -478,11 +495,14 @@ direct_start(struct gamma_state *state)
 	}
 
 	/* Allocate partition states */
-	if (state->partition_selected) {
-		state->partitions = ecalloc(1, sizeof(*state->partitions));
-		state->partitions[0].state.partition = state->selected_partition;
-		state->partitions[0].state.data = NULL;
-		state->npartitions = 1;
+	if (state->npartitions) {
+		state->partitions = ecalloc(state->npartitions, sizeof(*state->partitions));
+		for (i = 0; i < state->npartitions; i++) {
+			state->partitions[i].state.partition = state->selected_partitions[i];
+			state->partitions[i].state.data = NULL;
+		}
+		free(state->selected_partitions);
+		state->selected_partitions = NULL;
 	} else if (!state->site.partitions_available) {
 		if (state->partitions_are_graphics_cards)
 			weprintf(_("No graphics card found."));
@@ -908,6 +928,7 @@ direct_free(struct gamma_state *state)
 				libgamma_partition_destroy(&state->partitions[i].state);
 		free(state->partitions);
 	}
+	free(state->selected_partitions);
 	free(state->selected_crtcs);
 	if (state->selected_edids) {
 		for (i = 0; i < state->nedids; i++)