nkiss

commit e1ccb86fada2f6a5a50f86c33ea76dc9063bde85
parent 969db94dbd640891967a12b462f24b0b8d2c922b
Author: Nihal Jere <nihal@nihaljere.xyz>
Date:   Mon, 22 Feb 2021 21:23:08 -0600

pkg.*: add pkg_remove

Diffstat:
M
pkg.c
 | 
68
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
M
pkg.h
 | 
1
+

2 files changed, 69 insertions(+), 0 deletions(-)
diff --git a/pkg.c b/pkg.c
@@ -14,6 +14,74 @@
 #include "util.h"
 
 void
+pkg_remove(char *name)
+{
+    char manifestpath[PATH_LEN], etcsumspath[PATH_LEN], line[PATH_LEN],
+         etcsumstr[1024], etcsumhash[HASH_LEN], filehash[HASH_LEN];
+    FILE *manifest, *etcsums = NULL;
+    char *p;
+
+    if (snprintf(manifestpath, PATH_LEN, "%s/%s/manifest",
+                KISS_INSTALLED, name) >= PATH_LEN) {
+        die("%s: manifest path too long for %s", __func__, name);
+    }
+
+    /* no length check needed: "etcsums" is shorter than "manifest" */
+    snprintf(etcsumspath, PATH_LEN, "%s/%s/etcsums", KISS_INSTALLED, name);
+
+    if ((manifest = fopen(manifestpath, "r")) == NULL) {
+        die("%s: failed to open manifest for %s", __func__, name);
+    }
+
+    if (access(etcsumspath, F_OK) == 0 && !(etcsums = fopen(etcsumspath, "r"))) {
+        fclose(manifest);
+        die("%s: failed to open etcsums for %s", name);
+    }
+
+    while(fgets(line, PATH_LEN, manifest)) {
+        if ((p = strchr(line, '\n')) == NULL) {
+            fclose(manifest);
+            if (etcsums)
+                fclose(etcsums);
+            die("%s: path too long in manifest for %s", __func__, name);
+        }
+        *p = '\0';
+
+        /* /etc files are dealt with specially */
+        if (strncmp(line, "/etc/", sizeof("/etc/") - 1) == 0 && etcsums) {
+            if (!fgets(etcsumstr, 1024, etcsums)) {
+                fclose(manifest);
+                fclose(etcsums);
+                die("%s: bad etcsums for %s", __func__, name);
+            }
+
+            if (sha256_file(line, filehash) == -1)
+                die("%s: failed to hash %s", __func__, line);
+
+            sha256_fromstr(etcsumhash, etcsumstr);
+
+            /* if the file in /etc has been modified, don't remove it */
+            if (memcmp(etcsumhash, filehash, HASH_LEN) != 0)
+                continue;
+        }
+
+        /* we do rmdir first, as unlink won't tell us whether a file cannot be
+         * removed because it's a directory. */
+        if (rmdir(line) == -1) {
+            if (errno == ENOTEMPTY)
+                continue;
+
+            if (errno == ENOTDIR && unlink(line) == -1)
+                warn("%s: failed to remove %s:", __func__, line);
+        }
+    }
+
+    fclose(manifest);
+    if (etcsums)
+        fclose(etcsums);
+}
+
+void
 pkg_retrieve(struct source_t *sources)
 {
     for (int i = 0; sources[i].path[0] != '\0'; i++) {
diff --git a/pkg.h b/pkg.h
@@ -17,6 +17,7 @@ struct source_t {
     char checksum[HASH_LEN];
 };
 
+void pkg_remove(char *name);
 void pkg_retrieve(struct source_t *sources);
 int pkg_sources(char *repo, char *name, struct source_t *);
 void pkg_checksums_load(char *repo, char *name, struct source_t *);