specials: Read and search special files list

specials.txt is a temporary example file.

3 files changed, 171 insertions, 0 deletions

diff --git a/src/local.mk b/src/local.mk
index e6d77cc..5e8e4bf 100644
--- a/src/local.mk
+++ b/src/local.mk
@@ -8,6 +8,8 @@ opkg_opk_SOURCES += \
 	%reldir%/main.c \
 	%reldir%/opk.c \
 	%reldir%/opk.h \
+	%reldir%/specials.c \
+	%reldir%/specials.h \
 	%reldir%/ustar.c \
 	%reldir%/ustar.h
 
diff --git a/src/specials.c b/src/specials.c
new file mode 100644
index 0000000..8a9fac3
--- /dev/null
+++ b/src/specials.c
@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2023  Patrick McDermott
+ *
+ * This file is part of opkg-opkg.
+ *
+ * opkg-opkg is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * opkg-opkg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with opkg-opkg.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <inttypes.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "defs.h"
+#include "specials.h"
+
+struct opkg_opk_specials {
+	char                      type;
+	uint32_t                  devmajor;
+	uint32_t                  devminor;
+	char                     *name;
+	struct opkg_opk_specials *next;
+};
+
+static int
+_opkg_opk_specials_read_v1(FILE *fp, struct opkg_opk_specials **specials)
+{
+	struct opkg_opk_specials *special;
+
+	*specials = NULL;
+	fscanf(fp, "%*[^\n]\n");  /* Header line */
+	while (feof(fp) == 0) {
+		special = malloc(sizeof(*special));
+		if (special == NULL) {
+			opkg_opk_specials_free(*specials);
+			return OPKG_OPK_ERROR;
+		}
+/*		POSIX specifies the assignment-allocation character 'm', but ISO
+ *		C doesn't, so GCC prints a warning. */
+#		pragma GCC diagnostic push
+#		pragma GCC diagnostic ignored "-Wformat"
+		if (fscanf(fp, " %c %" SCNu32 " %" SCNu32 " %ms \n",
+					&special->type,
+					&special->devmajor, &special->devminor,
+					&special->name) != 4) {
+#		pragma GCC diagnostic pop
+			opkg_opk_specials_free(*specials);
+			return OPKG_OPK_ERROR;
+		}
+		if (special->type != 'c' && special->type != 'b') {
+			opkg_opk_specials_free(*specials);
+			return OPKG_OPK_ERROR;
+		}
+		special->next = *specials;
+		*specials = special;
+	}
+
+	return OPKG_OPK_OK;
+}
+
+int
+opkg_opk_specials_read(const char *file_name,
+		struct opkg_opk_specials **specials)
+{
+	FILE         *fp;
+	unsigned int  version;
+
+	fp = fopen(file_name, "r");
+	if (fp == NULL) {
+		return OPKG_OPK_ERROR;
+	}
+	if (fscanf(fp, " version = %u \n", &version) != 1) {
+		fclose(fp);
+		return OPKG_OPK_ERROR;
+	}
+	switch (version) {
+		case 1U:
+			if (_opkg_opk_specials_read_v1(fp, specials) !=
+					OPKG_OPK_OK) {
+				fclose(fp);
+				return OPKG_OPK_ERROR;
+			}
+			break;
+		default:
+			fclose(fp);
+			return OPKG_OPK_ERROR;
+	}
+
+	fclose(fp);  /* Just reading, so OK to ignore errors */
+	return OPKG_OPK_OK;
+}
+
+int
+opkg_opk_specials_find(struct opkg_opk_specials *specials, const char *find,
+		char *type, uint32_t *devmajor, uint32_t *devminor)
+{
+	for (; specials != NULL; specials = specials->next) {
+		if (strcmp(find, specials->name) == 0) {
+			*type     = specials->type;
+			*devmajor = specials->devmajor;
+			*devminor = specials->devminor;
+			return OPKG_OPK_OK;
+		}
+	}
+
+	return OPKG_OPK_END;
+}
+
+void
+opkg_opk_specials_free(struct opkg_opk_specials *specials)
+{
+	struct opkg_opk_specials *special;
+
+	while (specials != NULL) {
+		special = specials;
+		specials = specials->next;
+		free(special->name);
+		free(special);
+	}
+}
diff --git a/src/specials.h b/src/specials.h
new file mode 100644
index 0000000..2662f27
--- /dev/null
+++ b/src/specials.h
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2023  Patrick McDermott
+ *
+ * This file is part of opkg-opkg.
+ *
+ * opkg-opkg is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * opkg-opkg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with opkg-opkg.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef OPKG_OPK_SPECIALS_H_
+#define OPKG_OPK_SPECIALS_H_
+
+#include <stdint.h>
+
+struct opkg_opk_specials;
+
+int
+opkg_opk_specials_read(const char *file_name,
+		struct opkg_opk_specials **specials);
+
+int
+opkg_opk_specials_find(struct opkg_opk_specials *specials, const char *find,
+		char *type, uint32_t *devmajor, uint32_t *devminor);
+
+void
+opkg_opk_specials_free(struct opkg_opk_specials *specials);
+
+#endif  /* OPKG_OPK_SPECIALS_H_ */