Merging upstream version 2.0.3+dfsg (Closes: #923993, #1042533, #1045145).

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

2 files changed, 353 insertions, 0 deletions

diff --git a/src/libnetdata/paths/paths.c b/src/libnetdata/paths/paths.c
new file mode 100644
index 000000000..c68ee805f
--- /dev/null
+++ b/src/libnetdata/paths/paths.c
@@ -0,0 +1,327 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "paths.h"
+
+static int is_procfs(const char *path, char **reason) {
+#if defined(__APPLE__) || defined(__FreeBSD__)
+    (void)path;
+    (void)reason;
+#else
+    struct statfs stat;
+
+    if (statfs(path, &stat) == -1) {
+        if (reason)
+            *reason = "failed to statfs()";
+        return -1;
+    }
+
+#if defined PROC_SUPER_MAGIC
+    if (stat.f_type != PROC_SUPER_MAGIC) {
+        if (reason)
+            *reason = "type is not procfs";
+        return -1;
+    }
+#endif
+
+#endif
+
+    return 0;
+}
+
+static int is_sysfs(const char *path, char **reason) {
+#if defined(__APPLE__) || defined(__FreeBSD__)
+    (void)path;
+    (void)reason;
+#else
+    struct statfs stat;
+
+    if (statfs(path, &stat) == -1) {
+        if (reason)
+            *reason = "failed to statfs()";
+        return -1;
+    }
+
+#if defined SYSFS_MAGIC
+    if (stat.f_type != SYSFS_MAGIC) {
+        if (reason)
+            *reason = "type is not sysfs";
+        return -1;
+    }
+#endif
+
+#endif
+
+    return 0;
+}
+
+int verify_netdata_host_prefix(bool log_msg) {
+    if(!netdata_configured_host_prefix)
+        netdata_configured_host_prefix = "";
+
+    if(!*netdata_configured_host_prefix)
+        return 0;
+
+    char path[FILENAME_MAX];
+    char *reason = "unknown reason";
+    errno_clear();
+
+    strncpyz(path, netdata_configured_host_prefix, sizeof(path) - 1);
+
+    struct stat sb;
+    if (stat(path, &sb) == -1) {
+        reason = "failed to stat()";
+        goto failed;
+    }
+
+    if((sb.st_mode & S_IFMT) != S_IFDIR) {
+        errno = EINVAL;
+        reason = "is not a directory";
+        goto failed;
+    }
+
+    snprintfz(path, sizeof(path), "%s/proc", netdata_configured_host_prefix);
+    if(is_procfs(path, &reason) == -1)
+        goto failed;
+
+    snprintfz(path, sizeof(path), "%s/sys", netdata_configured_host_prefix);
+    if(is_sysfs(path, &reason) == -1)
+        goto failed;
+
+    if (netdata_configured_host_prefix && *netdata_configured_host_prefix) {
+        if (log_msg)
+            netdata_log_info("Using host prefix directory '%s'", netdata_configured_host_prefix);
+    }
+
+    return 0;
+
+failed:
+    if (log_msg)
+        netdata_log_error("Ignoring host prefix '%s': path '%s' %s", netdata_configured_host_prefix, path, reason);
+
+    netdata_configured_host_prefix = "";
+    return -1;
+}
+
+size_t filename_from_path_entry(char out[FILENAME_MAX], const char *path, const char *entry, const char *extension) {
+    if(unlikely(!path || !*path)) path = ".";
+    if(unlikely(!entry)) entry = "";
+
+    // skip trailing slashes in path
+    size_t len = strlen(path);
+    while(len > 0 && path[len - 1] == '/') len--;
+
+    // skip leading slashes in subpath
+    while(entry[0] == '/') entry++;
+
+    // if the last character in path is / and (there is a subpath or path is now empty)
+    // keep the trailing slash in path and remove the additional slash
+    char *slash = "/";
+    if(path[len] == '/' && (*entry || len == 0)) {
+        slash = "";
+        len++;
+    }
+    else if(!*entry) {
+        // there is no entry
+        // no need for trailing slash
+        slash = "";
+    }
+
+    return snprintfz(out, FILENAME_MAX, "%.*s%s%s%s%s", (int)len, path, slash, entry,
+                     extension && *extension ? "." : "",
+                     extension && *extension ? extension : "");
+}
+
+char *filename_from_path_entry_strdupz(const char *path, const char *entry) {
+    char filename[FILENAME_MAX];
+    filename_from_path_entry(filename, path, entry, NULL);
+    return strdupz(filename);
+}
+
+bool filename_is_dir(const char *filename, bool create_it) {
+    CLEAN_CHAR_P *buffer = NULL;
+
+    size_t max_links = 100;
+
+    bool is_dir = false;
+    struct stat st;
+    while(max_links && stat(filename, &st) == 0) {
+        if ((st.st_mode & S_IFMT) == S_IFDIR)
+            is_dir = true;
+        else if ((st.st_mode & S_IFMT) == S_IFLNK) {
+            max_links--;
+
+            if(!buffer)
+                buffer = mallocz(FILENAME_MAX);
+
+            char link_dst[FILENAME_MAX];
+            ssize_t l = readlink(filename, link_dst, FILENAME_MAX - 1);
+            if (l > 0) {
+                link_dst[l] = '\0';
+                strncpyz(buffer, link_dst, FILENAME_MAX - 1);
+                filename = buffer;
+                continue;
+            }
+        }
+
+        break;
+    }
+
+    if(!is_dir && create_it && max_links == 100 && mkdir(filename, 0750) == 0)
+        is_dir = true;
+
+    return is_dir;
+}
+
+bool path_entry_is_dir(const char *path, const char *entry, bool create_it) {
+    char filename[FILENAME_MAX];
+    filename_from_path_entry(filename, path, entry, NULL);
+    return filename_is_dir(filename, create_it);
+}
+
+bool filename_is_file(const char *filename) {
+    CLEAN_CHAR_P *buffer = NULL;
+
+    size_t max_links = 100;
+
+    bool is_file = false;
+    struct stat st;
+    while(max_links && stat(filename, &st) == 0) {
+        if((st.st_mode & S_IFMT) == S_IFREG)
+            is_file = true;
+        else if((st.st_mode & S_IFMT) == S_IFLNK) {
+            max_links--;
+
+            if(!buffer)
+                buffer = mallocz(FILENAME_MAX);
+
+            char link_dst[FILENAME_MAX];
+            ssize_t l = readlink(filename, link_dst, FILENAME_MAX - 1);
+            if(l > 0) {
+                link_dst[l] = '\0';
+                strncpyz(buffer, link_dst, FILENAME_MAX - 1);
+                filename = buffer;
+                continue;
+            }
+        }
+
+        break;
+    }
+
+    return is_file;
+}
+
+bool path_entry_is_file(const char *path, const char *entry) {
+    char filename[FILENAME_MAX];
+    filename_from_path_entry(filename, path, entry, NULL);
+    return filename_is_file(filename);
+}
+
+void recursive_config_double_dir_load(const char *user_path, const char *stock_path, const char *entry, int (*callback)(const char *filename, void *data, bool stock_config), void *data, size_t depth) {
+    if(depth > 3) {
+        netdata_log_error("CONFIG: Max directory depth reached while reading user path '%s', stock path '%s', subpath '%s'", user_path, stock_path,
+                          entry);
+        return;
+    }
+
+    if(!stock_path)
+        stock_path = user_path;
+
+    char *udir = filename_from_path_entry_strdupz(user_path, entry);
+    char *sdir = filename_from_path_entry_strdupz(stock_path, entry);
+
+    netdata_log_debug(D_HEALTH, "CONFIG traversing user-config directory '%s', stock config directory '%s'", udir, sdir);
+
+    DIR *dir = opendir(udir);
+    if (!dir) {
+        netdata_log_error("CONFIG cannot open user-config directory '%s'.", udir);
+    }
+    else {
+        struct dirent *de = NULL;
+        while((de = readdir(dir))) {
+            if(de->d_type == DT_DIR || de->d_type == DT_LNK) {
+                if( !de->d_name[0] ||
+                    (de->d_name[0] == '.' && de->d_name[1] == '\0') ||
+                    (de->d_name[0] == '.' && de->d_name[1] == '.' && de->d_name[2] == '\0')
+                ) {
+                    netdata_log_debug(D_HEALTH, "CONFIG ignoring user-config directory '%s/%s'", udir, de->d_name);
+                    continue;
+                }
+
+                if(path_entry_is_dir(udir, de->d_name, false)) {
+                    recursive_config_double_dir_load(udir, sdir, de->d_name, callback, data, depth + 1);
+                    continue;
+                }
+            }
+
+            if(de->d_type == DT_UNKNOWN || de->d_type == DT_REG || de->d_type == DT_LNK) {
+                size_t len = strlen(de->d_name);
+                if(path_entry_is_file(udir, de->d_name) &&
+                    len > 5 && !strcmp(&de->d_name[len - 5], ".conf")) {
+                    char *filename = filename_from_path_entry_strdupz(udir, de->d_name);
+                    netdata_log_debug(D_HEALTH, "CONFIG calling callback for user file '%s'", filename);
+                    callback(filename, data, false);
+                    freez(filename);
+                    continue;
+                }
+            }
+
+            netdata_log_debug(D_HEALTH, "CONFIG ignoring user-config file '%s/%s' of type %d", udir, de->d_name, (int)de->d_type);
+        }
+
+        closedir(dir);
+    }
+
+    netdata_log_debug(D_HEALTH, "CONFIG traversing stock config directory '%s', user config directory '%s'", sdir, udir);
+
+    dir = opendir(sdir);
+    if (!dir) {
+        netdata_log_error("CONFIG cannot open stock config directory '%s'.", sdir);
+    }
+    else {
+        if (strcmp(udir, sdir)) {
+            struct dirent *de = NULL;
+            while((de = readdir(dir))) {
+                if(de->d_type == DT_DIR || de->d_type == DT_LNK) {
+                    if( !de->d_name[0] ||
+                        (de->d_name[0] == '.' && de->d_name[1] == '\0') ||
+                        (de->d_name[0] == '.' && de->d_name[1] == '.' && de->d_name[2] == '\0')
+                    ) {
+                        netdata_log_debug(D_HEALTH, "CONFIG ignoring stock config directory '%s/%s'", sdir, de->d_name);
+                        continue;
+                    }
+
+                    if(path_entry_is_dir(sdir, de->d_name, false)) {
+                        // we recurse in stock subdirectory, only when there is no corresponding
+                        // user subdirectory - to avoid reading the files twice
+
+                        if(!path_entry_is_dir(udir, de->d_name, false))
+                            recursive_config_double_dir_load(udir, sdir, de->d_name, callback, data, depth + 1);
+
+                        continue;
+                    }
+                }
+
+                if(de->d_type == DT_UNKNOWN || de->d_type == DT_REG || de->d_type == DT_LNK) {
+                    size_t len = strlen(de->d_name);
+                    if(path_entry_is_file(sdir, de->d_name) && !path_entry_is_file(udir, de->d_name) &&
+                        len > 5 && !strcmp(&de->d_name[len - 5], ".conf")) {
+                        char *filename = filename_from_path_entry_strdupz(sdir, de->d_name);
+                        netdata_log_debug(D_HEALTH, "CONFIG calling callback for stock file '%s'", filename);
+                        callback(filename, data, true);
+                        freez(filename);
+                        continue;
+                    }
+
+                }
+
+                netdata_log_debug(D_HEALTH, "CONFIG ignoring stock-config file '%s/%s' of type %d", udir, de->d_name, (int)de->d_type);
+            }
+        }
+        closedir(dir);
+    }
+
+    netdata_log_debug(D_HEALTH, "CONFIG done traversing user-config directory '%s', stock config directory '%s'", udir, sdir);
+
+    freez(udir);
+    freez(sdir);
+}
diff --git a/src/libnetdata/paths/paths.h b/src/libnetdata/paths/paths.h
new file mode 100644
index 000000000..9c5a8a748
--- /dev/null
+++ b/src/libnetdata/paths/paths.h
@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef NETDATA_PATHS_H
+#define NETDATA_PATHS_H
+
+#include "../libnetdata.h"
+
+size_t filename_from_path_entry(char out[FILENAME_MAX], const char *path, const char *entry, const char *extension);
+char *filename_from_path_entry_strdupz(const char *path, const char *entry);
+
+bool filename_is_file(const char *filename);
+bool filename_is_dir(const char *filename, bool create_it);
+
+bool path_entry_is_file(const char *path, const char *entry);
+bool path_entry_is_dir(const char *path, const char *entry, bool create_it);
+
+void recursive_config_double_dir_load(
+    const char *user_path
+    , const char *stock_path
+    , const char *entry
+    , int (*callback)(const char *filename, void *data, bool stock_config)
+    , void *data
+    , size_t depth
+);
+
+#endif //NETDATA_PATHS_H