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Diffstat (limited to '')
| -rw-r--r-- | export.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/export.c b/export.c new file mode 100644 index 0000000..3e87521 --- /dev/null +++ b/export.c @@ -0,0 +1,271 @@ +/* Copyright (C) 2020 C. McEnroe <june@causal.agency> + * + * This program 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. + * + * This program 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 this program. If not, see <https://www.gnu.org/licenses/>. + */ + +#include <err.h> +#include <inttypes.h> +#include <limits.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sysexits.h> +#include <time.h> +#include <unistd.h> + +#include "archive.h" +#include "imap.h" + +static const char *uidPath(uint32_t uid, const char *type) { + static char buf[PATH_MAX]; + snprintf(buf, sizeof(buf), "UID/%" PRIu32 ".%s", uid, type); + return buf; +} + +static void flatten(struct List *flat, struct List nested) { + for (size_t i = 0; i < nested.len; ++i) { + if (nested.ptr[i].type == List) { + flatten(flat, nested.ptr[i].list); + } else { + listPush(flat, nested.ptr[i]); + } + } +} + +enum Atom exportThreads(FILE *imap, struct List threads) { + struct List uids = {0}; + flatten(&uids, threads); + for (size_t i = uids.len - 1; i < uids.len; --i) { + if (uids.ptr[i].type != Number) { + errx(EX_PROTOCOL, "invalid thread UID"); + } + uint32_t uid = uids.ptr[i].number; + int error = 0; + if (!error) error = access(uidPath(uid, "atom"), F_OK); + if (!error) error = access(uidPath(uid, "html"), F_OK); + if (!error) error = access(uidPath(uid, "mbox"), F_OK); + if (!error) { + uids.ptr[i] = uids.ptr[--uids.len]; + } + } + enum Atom tag = 0; + if (!uids.len) goto done; + + tag = atom("exportThreads"); + fprintf(imap, "%s UID FETCH ", Atoms[tag]); + for (size_t i = 0; i < uids.len; ++i) { + fprintf(imap, "%s%" PRIu32, (i ? "," : ""), uids.ptr[i].number); + } + fprintf( + imap, + " (" + "UID ENVELOPE " + "BODY[HEADER.FIELDS (" MBOX_HEADERS ")] BODY[TEXT]" + ")\r\n" + ); + +done: + listFree(uids); + return tag; +} + +static struct Address parseAddress(struct List list) { + if (list.len < 4) { + errx(EX_PROTOCOL, "missing address structure fields"); + } + struct Address addr = {0}; + if (list.ptr[0].type == String) { + // TODO: Decode UTF-8 in name. + addr.name = strdup(list.ptr[0].string); + if (!addr.name) err(EX_OSERR, "strdup"); + } + if (list.ptr[2].type == String) addr.mailbox = list.ptr[2].string; + if (list.ptr[3].type == String) addr.host = list.ptr[3].string; + return addr; +} + +static struct AddressList parseAddressList(struct List list) { + struct Address *addrs = calloc(list.len, sizeof(*addrs)); + if (!addrs) err(EX_OSERR, "calloc"); + for (size_t i = 0; i < list.len; ++i) { + if (list.ptr[i].type != List) { + errx(EX_PROTOCOL, "invalid address field"); + } + addrs[i] = parseAddress(list.ptr[i].list); + } + return (struct AddressList) { list.len, addrs }; +} + +static char *parseID(char *id) { + size_t len = strlen(id); + if (id[0] != '<' || !len || id[len - 1] != '>') { + errx(EX_PROTOCOL, "invalid message ID"); + } + id[len - 1] = '\0'; + return &id[1]; +} + +static struct Envelope parseEnvelope(struct List list) { + enum { + Date, Subject, From, Sender, ReplyTo, + To, Cc, Bcc, InReplyTo, MessageID, + EnvelopeLen, + }; + if (list.len < EnvelopeLen) { + errx(EX_PROTOCOL, "missing envelope structure fields"); + } + struct Envelope envelope = {0}; + + if (list.ptr[Date].type != String) { + errx(EX_PROTOCOL, "invalid envelope date field"); + } + const char *date = list.ptr[Date].string; + date = strptime(date, "%a, %e %b %Y %H:%M:%S %z", &envelope.date); + if (!date) errx(EX_PROTOCOL, "invalid envelope date format"); + + envelope.date.tm_isdst = -1; + envelope.utc = mktime(&envelope.date); + + if (list.ptr[Subject].type != String) { + errx(EX_PROTOCOL, "invalid envelope subject field"); + } + // TODO: Decode UTF-8 in subject. + envelope.subject = strdup(list.ptr[Subject].string); + if (!envelope.subject) err(EX_OSERR, "strdup"); + + for (size_t i = From; i <= Bcc; ++i) { + if (list.ptr[i].type == List) continue; + if (list.ptr[i].type == Atom && list.ptr[i].atom == AtomNil) { + list.ptr[i].type = List; + list.ptr[i].list = (struct List) {0}; + continue; + } + errx(EX_PROTOCOL, "invalid envelope address field"); + } + for (size_t i = From; i <= ReplyTo; ++i) { + if (!list.ptr[i].list.len || list.ptr[i].list.ptr[0].type != List) { + errx(EX_PROTOCOL, "invalid envelope address field"); + } + } + envelope.from = parseAddress(list.ptr[From].list.ptr[0].list); + envelope.sender = parseAddress(list.ptr[Sender].list.ptr[0].list); + envelope.replyTo = parseAddress(list.ptr[ReplyTo].list.ptr[0].list); + envelope.to = parseAddressList(list.ptr[To].list); + envelope.cc = parseAddressList(list.ptr[Cc].list); + envelope.bcc = parseAddressList(list.ptr[Bcc].list); + + if (list.ptr[InReplyTo].type == String) { + envelope.inReplyTo = parseID(list.ptr[InReplyTo].string); + } + if (list.ptr[MessageID].type != String) { + errx(EX_PROTOCOL, "invalid envelope message-id field"); + } + envelope.messageID = parseID(list.ptr[MessageID].string); + + return envelope; +} + +static enum Atom AtomBody; +static enum Atom AtomEnvelope; +static enum Atom AtomHeaderFields; +static enum Atom AtomText; +static enum Atom AtomUID; + +void exportData(struct List items) { + if (!AtomBody) AtomBody = atom("BODY"); + if (!AtomEnvelope) AtomEnvelope = atom("ENVELOPE"); + if (!AtomHeaderFields) AtomHeaderFields = atom("HEADER.FIELDS"); + if (!AtomText) AtomText = atom("TEXT"); + if (!AtomUID) AtomUID = atom("UID"); + + uint32_t uid = 0; + struct Envelope envelope = {0}; + char *header = NULL; + char *body = NULL; + + for (size_t i = 0; i + 1 < items.len; i += 2) { + enum Atom name; + if (items.ptr[i].type == Atom) { + name = items.ptr[i].atom; + } else if ( + items.ptr[i].type == List && + items.ptr[i].list.len && + items.ptr[i].list.ptr[0].type == Atom + ) { + name = items.ptr[i].list.ptr[0].atom; + } else { + errx(EX_PROTOCOL, "invalid data item name"); + } + + if (name == AtomBody) { + i--; + continue; + } else if (name == AtomUID) { + if (items.ptr[i + 1].type != Number) { + errx(EX_PROTOCOL, "invalid UID data item value"); + } + uid = items.ptr[i + 1].number; + } else if (name == AtomEnvelope) { + if (items.ptr[i + 1].type != List) { + errx(EX_PROTOCOL, "invalid ENVELOPE data item value"); + } + envelope = parseEnvelope(items.ptr[i + 1].list); + } else if (name == AtomHeaderFields) { + if (items.ptr[i + 1].type != String) { + errx(EX_PROTOCOL, "invalid BODY[HEADER.FIELDS] data item value"); + } + header = items.ptr[i + 1].string; + } else if (name == AtomText) { + if (items.ptr[i + 1].type != String) { + errx(EX_PROTOCOL, "invalid BODY[TEXT] data item value"); + } + body = items.ptr[i + 1].string; + } + } + + if (!uid) errx(EX_PROTOCOL, "missing UID data item"); + if (!envelope.subject) errx(EX_PROTOCOL, "missing ENVELOPE data item"); + if (!header) errx(EX_PROTOCOL, "missing BODY[HEADER.FIELDS] data item"); + if (!body) errx(EX_PROTOCOL, "missing BODY[TEXT] data item"); + + const char *path; + FILE *file; + int error; + + path = uidPath(uid, "mbox"); + file = fopen(path, "w"); + if (!file) err(EX_CANTCREAT, "%s", path); + error = mboxFrom(file) + || mboxHeader(file, header) + || mboxBody(file, body) + || fclose(file); + if (error) err(EX_IOERR, "%s", path); + + path = uidPath(uid, "html"); + file = fopen(path, "w"); + if (!file) err(EX_CANTCREAT, "%s", path); + error = htmlEnvelope(file, &envelope) + || fclose(file); + if (error) err(EX_IOERR, "%s", path); + + path = uidPath(uid, "atom"); + file = fopen(path, "w"); + if (!file) err(EX_CANTCREAT, "%s", path); + error = atomEnvelope(file, &envelope) + || fclose(file); + if (error) err(EX_IOERR, "%s", path); + + envelopeFree(envelope); +} |